1220:
DNS:*.m.wikiversity.org, DNS:*.m.wikivoyage.org, DNS:*.m.wiktionary.org, DNS:*.mediawiki.org, DNS:*.planet.wikimedia.org, DNS:*.wikibooks.org, DNS:*.wikidata.org, DNS:*.wikimedia.org, DNS:*.wikimediafoundation.org, DNS:*.wikinews.org, DNS:*.wikiquote.org, DNS:*.wikisource.org, DNS:*.wikiversity.org, DNS:*.wikivoyage.org, DNS:*.wiktionary.org, DNS:*.wmfusercontent.org, DNS:*.zero.wikipedia.org, DNS:mediawiki.org, DNS:w.wiki, DNS:wikibooks.org, DNS:wikidata.org, DNS:wikimedia.org, DNS:wikimediafoundation.org, DNS:wikinews.org, DNS:wikiquote.org, DNS:wikisource.org, DNS:wikiversity.org, DNS:wikivoyage.org, DNS:wiktionary.org, DNS:wmfusercontent.org, DNS:wikipedia.org X509v3 Extended Key Usage: TLS Web Server
Authentication, TLS Web Client Authentication X509v3 Subject Key Identifier: 28:2A:26:2A:57:8B:3B:CE:B4:D6:AB:54:EF:D7:38:21:2C:49:5C:36 X509v3 Authority Key Identifier: keyid:96:DE:61:F1:BD:1C:16:29:53:1C:C0:CC:7D:3B:83:00:40:E6:1A:7C
1272:
2014 GMT Not After : Feb 20 10:00:00 2024 GMT Subject: C=BE, O=GlobalSign nv-sa, CN=GlobalSign
Organization Validation CA - SHA256 - G2 Subject Public Key Info: Public Key Algorithm: rsaEncryption Public-Key: (2048 bit) Modulus: 00:c7:0e:6c:3f:23:93:7f:cc:70:a5:9d:20:c3:0e: ... Exponent: 65537 (0x10001) X509v3 extensions: X509v3 Key Usage: critical Certificate Sign, CRL Sign X509v3 Basic Constraints: critical CA:TRUE, pathlen:0 X509v3 Subject Key Identifier: 96:DE:61:F1:BD:1C:16:29:53:1C:C0:CC:7D:3B:83:00:40:E6:1A:7C X509v3 Certificate Policies: Policy: X509v3 Any Policy CPS:
1310:
1998 GMT Not After : Jan 28 12:00:00 2028 GMT Subject: C=BE, O=GlobalSign nv-sa, OU=Root CA, CN=GlobalSign Root CA Subject Public Key Info: Public Key
Algorithm: rsaEncryption Public-Key: (2048 bit) Modulus: 00:da:0e:e6:99:8d:ce:a3:e3:4f:8a:7e:fb:f1:8b: ... Exponent: 65537 (0x10001) X509v3 extensions: X509v3 Key Usage: critical Certificate Sign, CRL Sign X509v3 Basic Constraints: critical CA:TRUE X509v3 Subject Key Identifier: 60:7B:66:1A:45:0D:97:CA:89:50:2F:7D:04:CD:34:A8:FF:FC:FD:4B Signature Algorithm: sha1WithRSAEncryption d6:73:e7:7c:4f:76:d0:8d:bf:ec:ba:a2:be:34:c5:28:32:b5: ...
1203:
Nov 21 08:00:00 2016 GMT Not After : Nov 22 07:59:59 2017 GMT Subject: C=US, ST=California, L=San
Francisco, O=Wikimedia Foundation, Inc., CN=*.wikipedia.org Subject Public Key Info: Public Key Algorithm: id-ecPublicKey Public-Key: (256 bit) pub: 00:c9:22:69:31:8a:d6:6c:ea:da:c3:7f:2c:ac:a5: af:c0:02:ea:81:cb:65:b9:fd:0c:6d:46:5b:c9:1e: 9d:3b:ef ASN1 OID: prime256v1 NIST CURVE: P-256 X509v3 extensions: X509v3 Key Usage: critical Digital Signature, Key Agreement Authority Information Access: CA Issuers - URI:
1508:, they can convince a CA to sign a certificate with innocuous contents, where the hash of those contents is identical to the hash of another, malicious set of certificate contents, created by the attacker with values of their choosing. The attacker can then append the CA-provided signature to their malicious certificate contents, resulting in a malicious certificate that appears to be signed by the CA. Because the malicious certificate contents are chosen solely by the attacker, they can have different validity dates or hostnames than the innocuous certificate. The malicious certificate can even contain a "CA: true" field making it able to issue further trusted certificates.
332:(PKI) and X.509 certificates was the well known "which directory" problem. The problem is the client does not know where to fetch missing intermediate certificates because the global X.500 directory never materialized. The problem was mitigated by including all intermediate certificates in a request. For example, early web servers only sent the web server's certificate to the client. Clients that lacked an intermediate CA certificate or where to find them failed to build a valid path from the CA to the server's certificate. To work around the problem, web servers now send all the intermediate certificates along with the web server's certificate.
2252:
1096:
703:, if a certificate has several extensions restricting its use, all restrictions must be satisfied for a given use to be appropriate. The RFC gives the specific example of a certificate containing both keyUsage and extendedKeyUsage: in this case, both must be processed and the certificate can only be used if both extensions are coherent in specifying the usage of a certificate. For example,
593:, which is a set of values, together with either a critical or non-critical indication. A certificate-using system must reject the certificate if it encounters a critical extension that it does not recognize, or a critical extension that contains information that it cannot process. A non-critical extension may be ignored if it is not recognized, but must be processed if it is recognized.
1370:: CAs cannot technically restrict subordinate CAs from issuing certificates outside a limited namespaces or attribute set; this feature of X.509 is not in use. Therefore, a large number of CAs exist on the Internet, and classifying them and their policies is an insurmountable task. Delegation of authority within an organization cannot be handled at all, as in common business practice.
1112:
different private keys (from different CAs or different private keys from the same CA). So, although a single X.509 certificate can have only one issuer and one CA signature, it can be validly linked to more than one certificate, building completely different certificate chains. This is crucial for cross-certification between PKIs and other applications. See the following examples:
1267:. This certificate signed the end-entity certificate above, and was signed by the root certificate below. Note that the subject field of this intermediate certificate matches the issuer field of the end-entity certificate that it signed. Also, the "subject key identifier" field in the intermediate matches the "authority key identifier" field in the end-entity certificate.
669:, are used to indicate whether the certificate is a CA certificate and can certify or issue other certificates. A constraint can be marked as critical. If a constraint is marked critical, then an agent must fail to process the certificate if the agent does not understand the constraint. An agent can continue to process a non-critical constraint it does not understand.
1376:: Certificate chains that are the result of subordinate CAs, bridge CAs, and cross-signing make validation complex and expensive in terms of processing time. Path validation semantics may be ambiguous. The hierarchy with a third-party trusted party is the only model. This is inconvenient when a bilateral trust relationship is already in place.
220:, etc.), and is either signed by a certificate authority or is self-signed. When a certificate is signed by a trusted certificate authority, or validated by other means, someone holding that certificate can use the public key it contains to establish secure communications with another party, or validate documents
1569:
As of
January 1, 2016, the Baseline Requirements forbid issuance of certificates using SHA-1. As of early 2017, Chrome and Firefox reject certificates that use SHA-1. As of May 2017 both Edge and Safari are also rejecting SHA-1 certificate. Non-browser X.509 validators do not yet reject
1271:
Certificate: Data: Version: 3 (0x2) Serial Number: 04:00:00:00:00:01:44:4e:f0:42:47 Signature
Algorithm: sha256WithRSAEncryption Issuer: C=BE, O=GlobalSign nv-sa, OU=Root CA, CN=GlobalSign Root CA Validity Not Before: Feb 20 10:00:00
1202:
Certificate: Data: Version: 3 (0x2) Serial Number: 10:e6:fc:62:b7:41:8a:d5:00:5e:45:b6 Signature
Algorithm: sha256WithRSAEncryption Issuer: C=BE, O=GlobalSign nv-sa, CN=GlobalSign Organization Validation CA - SHA256 - G2 Validity Not Before:
1072:
Certificate chains are used in order to check that the public key (PK) contained in a target certificate (the first certificate in the chain) and other data contained in it effectively belongs to its subject. In order to ascertain this, the signature on the target certificate is verified by using the
759:
The CA/Browser Forum's PKI recognizes extended validation and many browsers provide visual feedback to the user to indicate a site provides an EV certificate. Other PKIs, like the
Internet's PKI (PKIX), do not place any special emphasis on extended validation. Tools using PKIX policies, like cURL and
1162:
To allow for graceful transition from the old signing key pair to the new signing key pair, the CA should issue a certificate that contains the old public key signed by the new private signing key and a certificate that contains the new public key signed by the old private signing key. Both of these
385:
X.509 certificates bind an identity to a public key using a digital signature. In the X.509 system, there are two types of certificates. The first is a CA certificate. The second is an end-entity certificate. A CA certificate can issue other certificates. The top level, self-signed CA certificate is
1346:
If the client only trusts certificates when CRLs are available, then they lose the offline capability that makes PKI attractive. So most clients do trust certificates when CRLs are not available, but in that case an attacker that controls the communication channel can disable the CRLs. Adam
Langley
1309:
Certificate: Data: Version: 3 (0x2) Serial Number: 04:00:00:00:00:01:15:4b:5a:c3:94 Signature
Algorithm: sha1WithRSAEncryption Issuer: C=BE, O=GlobalSign nv-sa, OU=Root CA, CN=GlobalSign Root CA Validity Not Before: Sep 1 12:00:00
335:
While PKIX refers to the IETF's or Internet's PKI standard, there are many other PKIs with different policies. For example, the US Government has its own PKI with its own policies, and the CA/Browser Forum has its own PKI with its own policies. The US Government's PKI is a massive book of over 2500
1172:
Since both cert1 and cert3 contain the same public key (the old one), there are two valid certificate chains for cert5: "cert5 → cert1" and "cert5 → cert3 → cert2", and analogously for cert6. This allows that old user certificates (such as cert5) and new certificates (such as cert6) can be trusted
1139:
In order to manage that user certificates existing in PKI 2 (like "User 2") are trusted by PKI 1, CA1 generates a certificate (cert2.1) containing the public key of CA2. Now both "cert2 and cert2.1 (in green) have the same subject and public key, so there are two valid chains for cert2.2 (User 2):
715:
Certification authorities operating under the CA/Browser Forum's PKI issue certificates with varying levels of validation. The different validations provide different levels of assurances that a certificate represents what it is supposed to. For example, a web server can be validated at the lowest
1425:
Like all businesses, CAs are subject to the legal jurisdictions they operate within, and may be legally compelled to compromise the interests of their customers and their users. Intelligence agencies have also made use of false certificates issued through extralegal compromise of CAs, such as
1111:
Examining how certificate chains are built and validated, it is important to note that a concrete certificate can be part of very different certificate chains (all of them valid). This is because several CA certificates can be generated for the same subject and public key, but be signed with
1219:
X509v3 Subject Alternative Name: DNS:*.wikipedia.org, DNS:*.m.mediawiki.org, DNS:*.m.wikibooks.org, DNS:*.m.wikidata.org, DNS:*.m.wikimedia.org, DNS:*.m.wikimediafoundation.org, DNS:*.m.wikinews.org, DNS:*.m.wikipedia.org, DNS:*.m.wikiquote.org, DNS:*.m.wikisource.org,
1561:
Exploiting a hash collision to forge X.509 signatures requires that the attacker be able to predict the data that the certificate authority will sign. This can be somewhat mitigated by the CA generating a random component in the certificates it signs, typically the serial number. The
1073:
PK contained in the following certificate, whose signature is verified using the next certificate, and so on until the last certificate in the chain is reached. As the last certificate is a trust anchor, successfully reaching it will prove that the target certificate can be trusted.
771:
cut into profits. During the race to the bottom CA's cut prices to lure consumers to purchase their certificates. As a result, profits were reduced and CA's dropped the level of validation they were performing to the point there were nearly no assurances on a certificate.
1486:, wrong implementations or by using integer overflows of the client's browsers, an attacker can include an unknown attribute in the CSR, which the CA will sign, which the client wrongly interprets as "CN" (OID=2.5.4.3). Dan Kaminsky demonstrated this at the 26th
467:
certificates from major certificate authorities will work instantly; in effect the browsers' developers determine which CAs are trusted third parties for the browsers' users. For example, Firefox provides a CSV and/or HTML file containing a list of Included CAs.
1185:, as stated in the Issuer field. Its Subject field describes Knowledge (XXG) as an organization, and its Subject Alternative Name (SAN) field for DNS describes the hostnames for which it could be used. The Subject Public Key Info field contains an
1406:, EV certificates do not add any additional security controls. Rather, EV certificates merely restore CA profits to levels prior to the Race to the Bottom by allowing a CA to charge more for a service they should have been providing all along.
1254:
In a TLS connection, a properly-configured server would provide the intermediate as part of the handshake. However, it's also possible to retrieve the intermediate certificate by fetching the "CA Issuers" URL from the end-entity certificate.
1284:
X509v3 Authority Key Identifier: keyid:60:7B:66:1A:45:0D:97:CA:89:50:2F:7D:04:CD:34:A8:FF:FC:FD:4B Signature Algorithm: sha256WithRSAEncryption 46:2a:ee:5e:bd:ae:01:60:37:31:11:86:71:74:b6:46:49:c8: ...
386:
sometimes called the Root CA certificate. Other CA certificates are called intermediate CA or subordinate CA certificates. An end-entity certificate identifies the user, like a person, organization or business. An end-entity certificate
676:, provides a bitmap specifying the cryptographic operations which may be performed using the public key contained in the certificate; for example, it could indicate that the key should be used for signatures but not for encipherment.
1503:
to work. When a public key infrastructure allows the use of a hash function that is no longer secure, an attacker can exploit weaknesses in the hash function to forge certificates. Specifically, if an attacker is able to produce a
1393:
The person or organization that purchases a certificate will often utilize the least expensive certification authority. In response, CA's have cut prices and removed more expensive validation checks in what is known as a
1364:: Identity claims (authenticate with an identifier), attribute claims (submit a bag of vetted attributes), and policy claims are combined in a single container. This raises privacy, policy mapping, and maintenance issues.
1060:
Each certificate (except the last one) is signed by the secret key corresponding to the next certificate in the chain (i.e. the signature of one certificate can be verified using the public key contained in the following
1302:. Its issuer and subject fields are the same, and its signature can be validated with its own public key. Validation of the trust chain has to end here. If the validating program has this root certificate in its
1421:
According to Peter Gutmann, "Users use an undefined certification request protocol to obtain a certificate which is published in an unclear location in a nonexistent directory with no real means to revoke
1417:
states in their CPS, "To the extent permitted by applicable law, Subscriber agreements, if applicable, disclaim warranties from Apple, including any warranty of merchantability or fitness for a particular
755:
to assert extended validation. There is no single OID to indicate extended validation, which complicates user agent programming. Each user agent must have a list of OIDs that indicate extended validation.
747:
Extended validation does not add any additional security controls, so the secure channel setup using an EV certificate is not "stronger" than a channel setup using a different level of validation like DV.
1383:
for a hostname doesn't prevent issuance of a lower-validation certificate valid for the same hostname, which means that the higher validation level of EV doesn't protect against man-in-the-middle attacks.
884:. These are generated for submission to certificate-authorities (CA). It includes key details of the requested certificate such as Common Name (/CN), subject, organization, state, country, as well as the
301:-like web of trust, but was rarely used that way as of 2004. The X.500 system has only been implemented by sovereign nations for state identity information sharing treaty fulfillment purposes, and the
1614:— Certification Path Building — guidance and recommendations for building X.509 public-key certification paths within applications (i.e., validating an end-entity certificate using a CA certificate)
1542:
a practical attack that allowed them to create a rogue Certificate Authority, accepted by all common browsers, by exploiting the fact that RapidSSL was still issuing X.509 certificates based on MD5.
683:, is used, typically on a leaf certificate, to indicate the purpose of the public key contained in the certificate. It contains a list of OIDs, each of which indicates an allowed use. For example,
3094:
1029:
is a standard for signing or encrypting (officially called "enveloping") data. Since the certificate is needed to verify signed data, it is possible to include them in the SignedData structure.
620:
goes bankrupt and its name is deleted from the country's public list. After some time another CA with the same name may register itself, even though it is unrelated to the first one. However,
1523:
and Benne de Weger demonstrated "how to use hash collisions to construct two X.509 certificates that contain identical signatures and that differ only in the public keys", achieved using a
348:. For example, if a PKI has a policy of only issuing certificates on Monday, then common tools like cURL and Wget will not enforce the policy and allow a certificate issued on a Tuesday.
1737:
security model and doesn't have need for certificates. However, the popular OpenSSH implementation does support a CA-signed identity model based on its own non-X.509 certificate format.
204:
An X.509 certificate binds an identity to a public key using a digital signature. A certificate contains an identity (a hostname, or an organization, or an individual) and a public key (
1434:. Another example is a revocation request of the CA of the Dutch government, because of a Dutch law passed in 2018, giving new powers for the Dutch intelligence and security services
1215:
Policy: 2.23.140.1.2.2 X509v3 Basic Constraints: CA:FALSE X509v3 CRL Distribution Points: Full Name: URI:
421:(DN) that is unique for the person, organization or business. The CSR may be accompanied by other credentials or proofs of identity required by the certificate authority.
336:
pages. If an organization's PKI diverges too much from that of the IETF or CA/Browser Forum, then the organization risks losing interoperability with common tools like
1143:
Similarly, CA2 can generate a certificate (cert1.1) containing the public key of CA1 so that user certificates existing in PKI 1 (like "User 1") are trusted by PKI 2.
616:
ITU-T introduced issuer and subject unique identifiers in version 2 to permit the reuse of issuer or subject name after some time. An example of reuse will be when a
2244:
1628:
1443:
Implementations suffer from design flaws, bugs, different interpretations of standards and lack of interoperability of different standards. Some problems are:
1479:
There are implementation errors with X.509 that allow e.g. falsified subject names using null-terminated strings or code injection attacks in certificates
1181:
This is an example of a decoded X.509 certificate that was used in the past by wikipedia.org and several other Knowledge (XXG) websites. It was issued by
2219:
305:'s Public-Key Infrastructure (X.509) (PKIX) working group has adapted the standard to the more flexible organization of the Internet. In fact, the term
3102:
1631:
formed the Public-Key Infrastructure (X.509) working group. The working group, concluded in June 2014, is commonly referred to as "PKIX." It produced
239:, which allows for certificates to be signed by intermediate CA certificates, which are, in turn, signed by other certificates, eventually reaching a
3175:
657:(and its predecessors) defines a number of certificate extensions which indicate how the certificate should be used. Most of them are arcs from the
1306:, the end-entity certificate can be considered trusted for use in a TLS connection. Otherwise, the end-entity certificate is considered untrusted.
3294:
1077:
236:
2646:
1545:
In April 2009 at the Eurocrypt Conference, Australian Researchers of Macquarie University presented "Automatic Differential Path Searching for
1104:
398:
390:
issue other certificates. An end-entity certificate is sometimes called a leaf certificate since no other certificates can be issued below it.
178:
1173:
indifferently by a party having either the new root CA certificate or the old one as trust anchor during the transition to the new CA keys.
589:
The Extensions field, if present, is a sequence of one or more certificate extensions. Each extension has its own unique ID, expressed as
1516:. Since the root certificate already had a self-signature, attackers could use this signature and use it for an intermediate certificate.
2575:
1674:
method for WiFi authentication. Any protocol that uses TLS, such as SMTP, POP, IMAP, LDAP, XMPP, and many more, inherently uses X.509.
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2375:
1986:
1591:
1403:
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488:
1968:
Following is a simplified view of the architectural model assumed by the Public-Key Infrastructure using X.509 (PKIX) specifications.
1227:
To validate this end-entity certificate, one needs an intermediate certificate that matches its Issuer and Authority Key Identifier:
2316:
1127:
A → B means "A is signed by B" (or, more precisely, "A is signed by the secret key corresponding to the public key contained in B").
235:, which are a means to distribute information about certificates that have been deemed invalid by a signing authority, as well as a
2450:
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of the certificate to get signed. These get signed by the CA and a certificate is returned. The returned certificate is the public
627:
Extensions were introduced in version 3. A CA can use extensions to issue a certificate only for a specific purpose (e.g. only for
2476:
2045:
3284:
3279:
3220:
1410:
792:
3043:
1821:"X.509: Information technology - Open Systems Interconnection - The Directory: Public-key and attribute certificate frameworks"
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1380:
402:
2196:
1604:(Personal Information Exchange Syntax Standard) — used to store a private key with the appropriate public key certificate
3289:
1582:(Cryptographic Message Syntax Standard — public keys with proof of identity for signed and/or encrypted message for PKI)
1549:". The researchers were able to deduce a method which increases the likelihood of a collision by several orders of magnitude.
270:
standard. The first tasks of it was providing users with secure access to information resources and avoiding a cryptographic
1303:
1009:
930:(SignedData, EnvelopedData) Message e.g. encrypted ("enveloped") file, message or MIME email letter. Defined in RFC 2311.
1746:
1552:
In February 2017, a group of researchers led by Marc Stevens produced a SHA-1 collision, demonstrating SHA-1's weakness.
1539:
1487:
1223:
Signature Algorithm: sha256WithRSAEncryption 8b:c3:ed:d1:9d:39:6f:af:40:72:bd:1e:18:5e:30:54:23:35: ...
959:
825:
800:
512:
255:
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232:
36:
Information technology - Open Systems Interconnection - The Directory: Public-key and attribute certificate frameworks
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recommends that no issuer and subject names be reused. Therefore, version 2 is not widely deployed in the Internet.
2833:
1713:
standard defines authentication either through TLS or through its own certificate profile. Both methods use X.509.
892:(which includes the public key but not the private key), which itself can be in a couple of formats but usually in
1453:
If it was turned on in all browsers by default, including code signing, it would probably crash the infrastructure
1786:
1049:
section 3.2) is a list of certificates (usually starting with an end-entity certificate) followed by one or more
741:
704:
329:
634:
In all versions, the serial number must be unique for each certificate issued by a specific CA (as mentioned in
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secret and using it to sign the CSR. The CSR contains information identifying the applicant and the applicant's
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1585:
1431:
410:
271:
186:
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1761:
1703:
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The Issuer of each certificate (except the last one) matches the Subject of the next certificate in the list
425:
414:
374:
286:, where anyone (not just special CAs) may sign and thus attest to the validity of others' key certificates.
1347:
of Google has said soft-fail CRL checks are like a safety belt that works except when you have an accident.
1088:
section 6, which involves additional checks, such as verifying validity dates on certificates, looking up
182:
2708:
1409:
Certification authorities attempt to deny almost all warranties to the user and relying parties in their
432:. The roles registration authority and certification authority are usually separate business units under
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2912:
2527:
2271:
1882:
1299:
1264:
1152:
1050:
617:
275:
1706:
often carry certificates to identify themselves or their owners. These certificates are in X.509 form.
1008:
PFX, predecessor of PKCS#12 (usually contains data in PKCS#12 format, e.g. with PFX files generated in
2502:
1635:
and other standards documentation on using and deploying X.509 in practice. In particular it produced
720:. Or a web server can be validated at a higher level of assurances using more detailed methods called
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2995:
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2637:
2291:
2142:
2024:
1923:
1862:
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1505:
1022:(CRL). Certificate Authorities produce these as a way to de-authorize certificates before expiration.
464:
456:
433:
251:
198:
100:
3248:- Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile
2859:
2645:(Technical report). Lucent Technologies, Bell Laboratories & Technische Universiteit Eindhoven.
1845:
Hesse, Peter; Cooper, Matt; Dzambasow, Yuriy A.; Joseph, Susan; Nicholas, Richard (September 2005).
1204:
1053:
certificates (usually the last one being a self-signed certificate), with the following properties:
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for X.509 certificates. Some of these extensions are also used for other data such as private keys.
751:
Extended validation is signaled in a certificate using X.509 v3 extension. Each CA uses a different
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1791:
1399:
519:
452:
283:
2128:
Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile
1909:
Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile
443:
can be distributed to all employees so that they can use the company PKI system. Browsers such as
1751:
1734:
1395:
1211:
X509v3 Certificate Policies: Policy: 1.3.6.1.4.1.4146.1.20 CPS:
1190:
781:
768:
429:
418:
209:
205:
2256:
2251:
1588:(TLS) and its predecessor SSL — cryptographic protocols for Internet secure communications.
1458:
DNs are complex and little understood (lack of canonicalization, internationalization problems)
3207:
2403:
2312:
2307:
Nash; Duane; Joseph; Brink (2001). "Key and Certificate Life Cycles. CA Certificate Renewal".
2238:
1535:
1483:
1095:
1000:, may contain certificate(s) (public) and private keys (password protected) in a single file.
752:
590:
496:
444:
221:
1130:
Certificates with the same color (that are not white/transparent) contain the same public key
940:
degenerated SignedData "certs-only" structure, without any data to sign. Defined in RFC 2311.
393:
An organization that wants a signed certificate requests one from a CA using a protocol like
3212:
3047:
2985:
2944:
2132:
2014:
1913:
1852:
1681:
1659:
1636:
1607:
1563:
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certificates, yet trust value in the eyes of security experts are diminishing. According to
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1068:: a certificate that you trust because it was delivered to you by some trustworthy procedure
1042:
740:, and a company like Example, LLC is the owner of the domain, and the owner was verified by
696:
650:
635:
597:
472:
440:
314:
1352:
CRLs are notably a poor choice because of large sizes and convoluted distribution patterns,
1216:
2379:
2220:"What is a Pem file and how does it differ from other OpenSSL Generated Key File Formats?"
1595:
1513:
1336:
1135:
Example 1: Cross-certification at root Certification Authority (CA) level between two PKIs
1089:
970:. The format used by Windows for certificate interchange. Supported by Java but often has
955:
480:
310:
3036:
Stefan Santesson; Michael Myers; Rich Ankey; Slava Galperin; Carlisle Adams (June 2013).
2428:
1167:. Note that these are in addition to the two self-signed certificates (one old, one new).
2782:
2255: This article incorporates text from this source, which is available under the
1566:
has required serial number entropy in its Baseline Requirements Section 7.1 since 2011.
3299:
2549:
1990:
1319:
1103:
290:
194:
3224:
2125:
Cooper, D.; Santesson, S.; Farrell, S.; Boeyen, S.; Housley, R.; Polk, W. (May 2008).
2092:
1906:
Cooper, D.; Santesson, S.; Farrell, S.; Boeyen, S.; Housley, R.; Polk, W. (May 2008).
1208:
3273:
1771:
1520:
500:
460:
3260:- decodes to an associative array whose keys correspond to X.509's ASN.1 description
3257:
1730:
1717:
1065:
628:
294:
279:
240:
170:
139:
3039:
X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSP
2734:
2693:
266:
X.509 was initially issued on July 3, 1988, and was begun in association with the
3231:
1643:
and its successor RFC 5280, which define how to use X.509 in Internet protocols.
1276:
X509v3 CRL Distribution Points: Full Name: URI:
687:
indicates that the key may be used on the server end of a TLS or SSL connection;
3245:
3238:
3124:
3081:
3077:
3073:
3069:
3060:
3037:
3023:
3019:
3015:
3011:
3007:
2998:
2975:
2957:
2938:
2182:
2178:
2174:
2170:
2166:
2162:
2158:
2154:
2145:
2126:
2027:
2008:
1963:
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1907:
1865:
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1710:
1685:
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1611:
1237:
C=BE, O=GlobalSign nv-sa, CN=GlobalSign Organization Validation CA - SHA256 - G2
1085:
1046:
733:
700:
654:
639:
601:
492:
476:
337:
318:
225:
727:
In practice, a DV certificate means a certificate was issued for a domain like
2534:
1699:
1182:
906:
response to CSR. Contains the newly-signed certificate, and the CA's own cert.
362:
2639:
On the possibility of constructing meaningful hash collisions for public keys
289:
Version 3 of X.509 includes the flexibility to support other topologies like
2757:
2756:
Marc Stevens; Elie Bursztein; Pierre Karpman; Ange Albertini; Yarik Markov.
2671:
2053:
2010:
Internet X.509 Public Key Infrastructure Operational Protocols: FTP and HTTP
1427:
1414:
1189:
public key, while the signature at the bottom was generated by GlobalSign's
916:
Digital Signature. May contain the original signed file or message. Used in
424:
The CSR will be validated using a Registration Authority (RA), and then the
2885:
2404:"Everything you Never Wanted to Know about PKI but were Forced to Find Out"
511:
The structure foreseen by the standards is expressed in a formal language,
2067:
3199:
2358:
1720:
code signing system uses X.509 to identify authors of computer programs.
1273:
1212:
406:
1512:
MD2-based certificates were used for a long time and were vulnerable to
3241:- Internet X.509 Public Key Infrastructure: Certification Path Building
1671:
1076:
The description in the preceding paragraph is a simplified view on the
767:
states CA's created EV certificates to restore profit levels after the
607:
The inner format of issuer and subject unique identifiers specified in
448:
298:
217:
1820:
608:
150:
3052:
2990:
2949:
2137:
2019:
1918:
1857:
1848:
Internet X.509 Public Key Infrastructure: Certification Path Building
1724:
1667:
1601:
1473:
Attributes should not be made critical because it makes clients crash
1277:
997:
954:
SignedData structure without data, just certificate(s) bundle and/or
917:
873:
796:
736:. An EV certificate means a certificate was issued for a domain like
463:
come with a predetermined set of root certificates pre-installed, so
1281:
185:. X.509 certificates are used in many Internet protocols, including
17:
3176:"How To Create an SSH CA to Validate Hosts and Clients with Ubuntu"
3150:
1801:
1677:
1655:
1579:
1546:
1355:
Ambiguous OCSP semantics and lack of historical revocation status,
1186:
1102:
1094:
1026:
963:
951:
937:
927:
913:
903:
847:
267:
247:
213:
190:
129:
118:
90:
3254:- can be used to decode and examine an encoded CSR or certificate
1263:
This is an example of an intermediate certificate belonging to a
1205:
http://secure.globalsign.com/cacert/gsorganizationvalsha2g2r1.crt
760:
Wget, simply treat an EV certificate like any other certificate.
2981:
1695:
defines its own profile of X.509 for use in the cable industry.
1476:
Unspecified length of attributes lead to product-specific limits
621:
484:
345:
341:
302:
3251:
1193:
private key. (The signatures in these examples are truncated.)
1041:(see the equivalent concept of "certification path" defined by
1528:
428:
will issue a certificate binding a public key to a particular
313:
profile of the X.509 v3 certificate standard, as specified in
661:
OID. Some of the most common, defined in section 4.2.1, are:
2528:"Certification Authority — Certification Practice Statement"
1598:(CRL) — this is to check certificate revocation status
1247:
96:DE:61:F1:BD:1C:16:29:53:1C:C0:CC:7D:3B:83:00:40:E6:1A:7C
1124:
Each box represents a certificate, with its Subject in bold
828:
form, but Base64-encoded certificates are common too (see
487:-approved way of checking a certificate's validity is the
417:
that is used to verify the signature of the CSR - and the
2364:. Computer Security Journal (Volume XVI, Number 1, 2000).
2336:"Web Services Security X.509 Token Profile Version 1.1.1"
1727:
industrial automation communication standard uses X.509.
1467:
Key usage ignored, first certificate in a list being used
1318:
There are a number of publications about PKI problems by
1280:
Authority Information Access: OCSP - URI:
3095:"PKCS 12: Personal Information Exchange Syntax Standard"
2707:
Cameron McDonald; Philip Hawkes; Josef Pieprzyk (2009).
1217:
http://crl.globalsign.com/gs/gsorganizationvalsha2g2.crl
278:(CAs) for issuing the certificates. This contrasts with
246:
X.509 is defined by the ITU's "Standardization Sector" (
2977:
The Transport Layer Security (TLS) Protocol Version 1.2
2050:
Apple Developer Documentation: Uniform Type Identifiers
1670:(Secure Multipurpose Internet Mail Extensions) and the
27:
Standard defining the format of public key certificates
2451:"Security Systems Business Plan Sample [2021]"
1647:
Major protocols and standards using X.509 certificates
646:
Extensions informing a specific usage of a certificate
2886:"Safari and WebKit do not support SHA-1 certificates"
2696:. International Association for Cryptologic Research.
495:
enabled OCSP checking by default, as did versions of
3125:"Public-Key Infrastructure (X.509) (pkix) - Charter"
2035:sec. 4: MIME registrations.
2093:"Bug 110161 - (ocspdefault) enable OCSP by default"
1209:
http://ocsp2.globalsign.com/gsorganizationvalsha2g2
1140:"cert2.2 → cert2" and "cert2.2 → cert2.1 → cert1".
967:
881:
855:
851:
808:
804:
707:uses both extensions to specify certificate usage.
691:
indicates that the key may be used to secure email.
373:
361:
197:. They are also used in offline applications, like
145:
135:
124:
114:
106:
96:
86:
66:
48:
40:
2674:. Eindhoven University of Technology. 16 June 2011
2477:"Sub-Prime PKI: Attacking Extended Validation SSL"
309:usually refers to the IETF's PKIX certificate and
2940:PKCS #7: Cryptographic Message Syntax Version 1.5
1358:Revocation of root certificates is not addressed,
1447:Many implementations turn off revocation check:
1398:. The Race to the Bottom is partly addressed by
1335:Use of blocklisting invalid certificates (using
2636:Lenstra, Arjen; de Weger, Benne (19 May 2005).
2475:Michael Zusman; Alexander Sotirov (July 2009).
1482:By using illegal 0x80 padded subidentifiers of
1099:Example 1: Cross-certification between two PKIs
982:way to include certification-path certificates.
1981:
1979:
1977:
1975:
1629:National Institute of Standards and Technology
2273:Understanding Certification Path Construction
1163:certificates are self-issued, but neither is
1154:Understanding Certification Path Construction
850:. May be in DER or PEM form that starts with
610:X.520 The Directory: Selected attribute types
399:Simple Certificate Enrollment Protocol (SCEP)
274:. It assumes a strict hierarchical system of
8:
2581:. Institute For Disruptive Studies. Blackhat
2293:Qualified Subordination Deployment Scenarios
1464:Name and policy constraints hardly supported
731:after someone responded to an email sent to
356:
30:
2576:"More Tricks for Defeating SSL in Practice"
2503:"Extended Validation Certificates are Dead"
2394:
2392:
2243:: CS1 maint: numeric names: authors list (
1499:Digital signature systems depend on secure
1450:Seen as obstacle, policies are not enforced
254:), in ITU-T Study Group 17 and is based on
3213:X.509 implementation notes and style guide
2120:
2118:
2116:
2114:
2112:
2110:
1033:Certificate chains and cross-certification
716:level of assurances using an email called
29:
3051:
2989:
2948:
2550:"Logius: Dutch Government CA trust issue"
2309:PKI: Implementing and Managing E-Security
2136:
2018:
1917:
1856:
1840:
1838:
2330:
2328:
2290:"Cross-Certification Between Root CAs".
1557:Mitigations for cryptographic weaknesses
1229:
1812:
1470:Enforcement of custom OIDs is difficult
1388:Problems with certification authorities
920:for email signing. Defined in RFC 2311.
846:– exported private key as specified in
596:The structure of version 1 is given in
479:also include standards for certificate
237:certification path validation algorithm
193:, the secure protocol for browsing the
2974:T. Dierks; E. Rescorla (August 2008).
2429:"Revocation checking and Chrome's CRL"
2385:. IEEE Computer (Volume:35, Issue: 8).
2236:
1411:Certification Practice Statement (CPS)
1274:https://www.globalsign.com/repository/
1213:https://www.globalsign.com/repository/
1064:The last certificate in the list is a
978:style certificates, this format has a
355:
181:(ITU) standard defining the format of
2860:"Microsoft Security Advisory 4010323"
2763:. CWI Amsterdam & Google Research
2007:Housley, R.; Hoffman, P. (May 1999).
1078:certification path validation process
958:(rarely) but not a private key. Uses
856:-----BEGIN ENCRYPTED PRIVATE KEY-----
405:. The organization first generates a
403:Certificate Management Protocol (CMP)
179:International Telecommunication Union
7:
2834:"The end of SHA-1 on the Public Web"
2758:"The first collision for full SHA-1"
1381:Extended Validation (EV) certificate
1242:
1232:
569:Subject Unique Identifier (optional)
297:. It can be used in a peer-to-peer,
3252:CSR Decoder and Certificate Decoder
2911:Daniel Stenburg (10 January 2017).
2807:Andrew Whalley (16 November 2016).
2714:. Macquarie University and Qualcomm
2311:. RSA Press - Osborne/McGraw-Hill.
1883:"Monumental Cybersecurity Blunders"
882:-----BEGIN CERTIFICATE REQUEST-----
566:Issuer Unique Identifier (optional)
3264:Understanding Digital Certificates
3223:. RSA Laboratories. Archived from
3101:. RSA Laboratories. Archived from
2380:"PKI: it's not dead, just resting"
2197:"All About Certificate Extensions"
1688:profile for authenticating peers.
1592:Online Certificate Status Protocol
1538:and Marc Stevens presented at the
1278:http://crl.globalsign.net/root.crl
659:joint-iso-ccitt(2) ds(5) id-ce(29)
489:Online Certificate Status Protocol
375:Uniform Type Identifier (UTI)
25:
3131:. Internet Engineering Task Force
2783:"Baseline Requirements Documents"
2735:"SHA-1 Collision Attacks Now 252"
2609:Dan Kaminsky (29 December 2009).
2427:Langley, Adam (5 February 2012).
2357:Carl Ellison and Bruce Schneier.
1282:http://ocsp.globalsign.com/rootr1
1147:Example 2: CA certificate renewal
1107:Example 2: CA certificate renewal
395:Certificate Signing Request (CSR)
323:Public Key Infrastructure (X.509)
258:(ASN.1), another ITU-T standard.
2652:from the original on 14 May 2013
2501:Hunt, Troy (17 September 2018).
2250:
1693:OpenCable security specification
1298:root certificate representing a
974:as an extension instead. Unlike
854:. The encrypted key starts with
793:Privacy-enhanced Electronic Mail
780:There are several commonly used
711:Extended Validation certificates
3044:Internet Engineering Task Force
2913:"Lesser HTTPS for non-browsers"
2599:Rec. ITU-T X.690, clause 8.19.2
2270:Lloyd, Steve (September 2002).
1625:Internet Engineering Task Force
880:(CSR). In PEM form starts with
776:Certificate filename extensions
582:Certificate Signature Algorithm
483:(CRL) implementations. Another
3295:ITU-T X Series Recommendations
2809:"SHA-1 Certificates in Chrome"
2672:"MD5 considered harmful today"
2195:Nelson B Boyard (9 May 2002).
803:certificate, enclosed between
1:
2218:sysadmin1138 (May 19, 2009).
1160:. PKI Forum. September 2002.
1006:Personal Information eXchange
518:The structure of an X.509 v3
436:to reduce the risk of fraud.
52:1.0 at November 25, 1988
2733:Dennis Dwyer (2 June 2009).
1747:Abstract Syntax Notation One
1540:Chaos Communication Congress
1501:cryptographic hash functions
1488:Chaos Communication Congress
1461:rfc822Name has two notations
1326:and other security experts.
513:Abstract Syntax Notation One
256:Abstract Syntax Notation One
233:certificate revocation lists
2813:Google Online Security Blog
1777:PKI Resource Query Protocol
1020:Certificate Revocation List
878:Certificate Signing Request
852:-----BEGIN PRIVATE KEY-----
805:-----BEGIN CERTIFICATE-----
321:, commonly called PKIX for
3316:
3221:"Crypto FAQ from RSA Labs"
3204:Peter Gutmann's articles:
3084:.
3026:.
2574:Moxie Marlinspike (2009).
2185:.
507:Structure of a certificate
439:An organization's trusted
2943:. Network Working Group.
2617:. Der Chaos Computer Club
2296:. Microsoft. August 2009.
2013:. Network Working Group.
1851:. Network Working Group.
1787:Public Key Infrastructure
1432:man-in-the-middle attacks
1243:Authority Key Identifier
1177:Sample X.509 certificates
809:-----END CERTIFICATE-----
742:Articles of Incorporation
330:Public Key Infrastructure
189:, which is the basis for
44:In force (Recommendation)
35:
3258:phpseclib: X.509 Decoder
2937:B Kaliski (March 1998).
2611:"26C3: Black Ops Of PKI"
1666:profile of X.509, as do
1627:in conjunction with the
1586:Transport Layer Security
1495:Cryptographic weaknesses
1400:Extended Validation (EV)
1330:Architectural weaknesses
1294:This is an example of a
1259:Intermediate certificate
966:or PEM that starts with
722:Extended Validation (EV)
555:Subject Public Key Info
363:Internet media type
272:man-in-the-middle attack
3285:Public-key cryptography
3280:Cryptographic protocols
3200:ITU-T's X.509 standards
1782:Public-key cryptography
1762:Communications security
1574:PKI standards for X.509
753:Object Identifier (OID)
629:signing digital objects
591:object identifier (OID)
426:certification authority
379:public.x509-certificate
276:certificate authorities
183:public key certificates
3232:Secure code guidelines
3006:Obsoleted by RFC
2771:– via Shattered.
2737:. SecureWorks Insights
2709:"SHA-1 collisions now"
1991:"Engineering Security"
1718:Microsoft Authenticode
1197:End-entity certificate
1108:
1100:
718:Domain Validation (DV)
695:In general when using
572:Extensions (optional)
535:Signature Algorithm ID
54:; 35 years ago
3290:ITU-T recommendations
3072:. Obsoletes RFC
3010:; obsoletes RFC
2838:Mozilla Security Blog
2173:. Obsoletes RFC
1954:. Obsoletes RFC
1594:(OCSP) / certificate
1439:Implementation issues
1300:certificate authority
1265:certificate authority
1106:
1098:
968:-----BEGIN PKCS7-----
585:Certificate Signature
368:application/pkix-cert
224:by the corresponding
199:electronic signatures
128:ISO/IEC 9594-8:2020,
74:; 2 years ago
72:October 14, 2021
3227:on 30 December 2006.
3068:Updated by RFC
2153:Updated by RFC
1934:Updated by RFC
1797:Trusted timestamping
1767:Information security
1757:Code Access Security
1570:SHA-1 certificates.
824:– usually in binary
679:Extended Key Usage,
558:Public Key Algorithm
434:separation of duties
328:An early issue with
101:ITU-T Study Group 17
3151:"Pkix Status Pages"
3080:. Updates RFC
3022:; updates RFC
1792:Time stamp protocol
1362:Aggregation problem
1120:In these diagrams:
782:filename extensions
665:Basic Constraints,
520:digital certificate
358:
231:X.509 also defines
32:
3066:Proposed Standard.
2840:. 23 February 2017
2537:. August 19, 2016.
2359:"Top 10 PKI risks"
2151:Proposed Standard.
2033:Proposed Standard.
1932:Proposed Standard.
1752:Certificate policy
1735:Trust On First Use
1619:PKIX Working Group
1490:"Black OPs of PKI"
1484:object identifiers
1396:Race to the Bottom
1374:Federation problem
1368:Delegation problem
1109:
1101:
769:Race to the Bottom
561:Subject Public Key
430:distinguished name
419:Distinguished Name
3266:Microsoft TechNet
2431:. Imperial Violet
2046:"x509Certificate"
1733:generally uses a
1536:Alexander Sotirov
1252:
1251:
1039:certificate chain
858:and may have the
445:Internet Explorer
441:root certificates
383:
382:
357:X.509 certificate
307:X.509 certificate
262:History and usage
167:
166:
125:Related standards
16:(Redirected from
3307:
3228:
3188:
3187:
3185:
3183:
3172:
3166:
3165:
3163:
3161:
3147:
3141:
3140:
3138:
3136:
3129:IETF Datatracker
3121:
3115:
3114:
3112:
3110:
3091:
3085:
3064:
3055:
3053:10.17487/RFC6960
3033:
3027:
3002:
2993:
2991:10.17487/RFC5246
2971:
2965:
2961:
2952:
2950:10.17487/RFC2315
2934:
2928:
2927:
2925:
2923:
2908:
2902:
2901:
2899:
2897:
2892:. 16 August 2018
2882:
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2845:
2830:
2824:
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2804:
2798:
2797:
2795:
2793:
2787:CA Browser Forum
2779:
2773:
2772:
2770:
2768:
2762:
2753:
2747:
2746:
2744:
2742:
2730:
2724:
2723:
2721:
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2713:
2704:
2698:
2697:
2694:"Eurocrypt 2009"
2690:
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2683:
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2560:
2548:van Pelt, Cris.
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2192:
2186:
2149:
2140:
2138:10.17487/RFC5280
2122:
2105:
2104:
2102:
2100:
2089:
2083:
2082:
2080:
2078:
2068:"CA:IncludedCAs"
2064:
2058:
2057:
2042:
2036:
2031:
2022:
2020:10.17487/RFC2585
2004:
1998:
1997:
1995:
1983:
1970:
1930:
1921:
1919:10.17487/RFC5280
1903:
1897:
1896:
1894:
1893:
1879:
1873:
1869:
1860:
1858:10.17487/RFC4158
1842:
1833:
1832:
1830:
1828:
1817:
1564:CA/Browser Forum
1525:collision attack
1514:preimage attacks
1290:Root certificate
1248:
1238:
1230:
1169:
1159:
1017:
1003:
995:
991:
987:
977:
973:
969:
949:
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857:
853:
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810:
806:
790:
763:Security expert
739:
735:
730:
690:
686:
682:
675:
668:
660:
613:recommendation.
541:Validity period
359:
222:digitally signed
163:
160:
158:
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154:
152:
82:
80:
75:
62:
60:
55:
33:
21:
3315:
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3309:
3308:
3306:
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3270:
3269:
3219:
3208:Overview of PKI
3196:
3191:
3181:
3179:
3174:
3173:
3169:
3159:
3157:
3149:
3148:
3144:
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3123:
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3108:
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3093:
3092:
3088:
3035:
3034:
3030:
2984:TLS workgroup.
2973:
2972:
2968:
2936:
2935:
2931:
2921:
2919:
2910:
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2895:
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2655:
2653:
2649:
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2635:
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2630:
2620:
2618:
2615:CCC Events Blog
2608:
2607:
2603:
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2594:
2584:
2582:
2578:
2573:
2572:
2568:
2558:
2556:
2547:
2546:
2542:
2533:. Version 6.1.
2530:
2526:
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2511:
2509:
2500:
2499:
2495:
2485:
2483:
2479:
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1596:revocation list
1576:
1559:
1497:
1441:
1430:, to carry out
1413:. For example,
1390:
1379:Issuance of an
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1316:
1311:
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689:{ id-pkix 3 4 }
688:
685:{ id-pkix 3 1 }
684:
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522:is as follows:
509:
481:revocation list
369:
354:
264:
149:
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76:
73:
71:
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56:
53:
49:First published
28:
23:
22:
15:
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3202:
3195:
3194:External links
3192:
3190:
3189:
3178:. DigitalOcean
3167:
3142:
3116:
3105:on 6 July 2017
3086:
3028:
2966:
2963:Informational.
2929:
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2877:
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2774:
2748:
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2400:Gutmann, Peter
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1999:
1989:(April 2014).
1987:Gutmann, Peter
1971:
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1871:Informational.
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1531:hash function.
1517:
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529:Version Number
508:
505:
499:from at least
409:, keeping the
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263:
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115:Base standards
112:
111:
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103:
98:
94:
93:
88:
84:
83:
68:
67:Latest version
64:
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2890:Apple Support
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2376:Peter Gutmann
2371:
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2318:0-07-213123-3
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1698:Devices like
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1518:
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761:
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531:
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316:
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304:
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292:
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285:
282:models, like
281:
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259:
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249:
244:
242:
238:
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3225:the original
3180:. Retrieved
3170:
3158:. Retrieved
3154:
3145:
3133:. Retrieved
3128:
3119:
3107:. Retrieved
3103:the original
3098:
3089:
3065:
3038:
3031:
3003:
2976:
2969:
2962:
2939:
2932:
2920:. Retrieved
2916:
2906:
2896:10 September
2894:. Retrieved
2889:
2880:
2868:. Retrieved
2863:
2854:
2842:. Retrieved
2837:
2828:
2816:. Retrieved
2812:
2802:
2790:. Retrieved
2786:
2777:
2767:10 September
2765:. Retrieved
2751:
2739:. Retrieved
2728:
2718:10 September
2716:. Retrieved
2702:
2688:
2678:29 September
2676:. Retrieved
2666:
2656:28 September
2654:. Retrieved
2638:
2631:
2621:29 September
2619:. Retrieved
2614:
2604:
2595:
2585:10 September
2583:. Retrieved
2569:
2557:. Retrieved
2553:
2543:
2522:
2510:. Retrieved
2507:TroyHunt.com
2506:
2496:
2486:10 September
2484:. Retrieved
2470:
2459:. Retrieved
2457:. 2014-01-27
2454:
2445:
2433:. Retrieved
2422:
2410:. Retrieved
2370:
2352:
2340:. Retrieved
2308:
2302:
2292:
2285:
2279:. PKI Forum.
2272:
2265:
2257:CC BY-SA 2.5
2249:
2227:. Retrieved
2224:Server Fault
2223:
2213:
2203:10 September
2201:. Retrieved
2190:
2150:
2127:
2097:. Retrieved
2087:
2075:. Retrieved
2072:Mozilla Wiki
2071:
2062:
2049:
2040:
2032:
2009:
2002:
1967:
1931:
1908:
1901:
1890:. Retrieved
1887:circleid.com
1886:
1877:
1870:
1847:
1825:. Retrieved
1815:
1729:
1722:
1715:
1708:
1697:
1690:
1680:can use the
1676:
1650:
1622:
1568:
1560:
1498:
1442:
1373:
1367:
1361:
1317:
1293:
1262:
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1180:
1171:
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1153:
1150:
1142:
1138:
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1075:
1071:
1066:trust anchor
1061:certificate)
1038:
1036:
1025:
1005:
979:
889:
885:
779:
762:
758:
750:
746:
726:
721:
717:
714:
694:
681:{ id-ce 37 }
674:{ id-ce 15 }
667:{ id-ce 19 }
649:
633:
626:
615:
609:
606:
595:
588:
552:Subject name
526:Certificate
517:
510:
470:
438:
423:
392:
387:
384:
352:Certificates
338:web browsers
334:
327:
322:
306:
288:
280:web of trust
265:
245:
241:trust anchor
230:
203:
174:
171:cryptography
168:
140:Cryptography
87:Organization
2866:. Microsoft
2741:24 February
2512:26 February
2412:14 November
1711:WS-Security
1700:smart cards
1304:trust store
1296:self-signed
1207:OCSP - URI:
1165:self-signed
890:certificate
738:example.com
729:example.com
672:Key Usage,
538:Issuer Name
503:and later.
493:Firefox 3.0
471:X.509 and
411:private key
226:private key
3274:Categories
3155:IETF Tools
2917:Daniel Hax
2559:31 October
2535:Apple, Inc
2482:. Blackhat
2461:2021-06-30
2455:OGScapital
2435:2 February
2229:19 October
2077:17 January
1892:2022-09-03
1827:6 November
1808:References
1183:GlobalSign
886:public key
862:extension.
544:Not Before
415:public key
79:2021-10-14
59:1988-11-25
3244:RFC
3237:RFC
3135:1 October
3004:Obsolete.
2199:. Mozilla
2095:. Mozilla
2054:Apple Inc
1534:In 2008,
1519:In 2005,
1428:DigiNotar
1418:purpose".
1415:Apple Inc
972:.keystore
948:.keystore
547:Not After
515:(ASN.1).
97:Committee
3182:19 March
3160:10 March
3109:19 March
3046:(IETF).
2922:19 March
2844:19 March
2818:19 March
2792:19 March
2647:Archived
2554:Bugzilla
2342:14 March
2259:license.
2239:cite web
2099:17 March
1741:See also
1658:use the
1314:Security
1116:Examples
962:form or
799:encoded
491:(OCSP).
407:key pair
159:/T-REC-X
3099:EMC.com
2864:Technet
2338:. Oasis
1672:EAP-TLS
1652:TLS/SSL
1527:on the
1233:Issuer
1092:, etc.
998:PKCS#12
994:.pkcs12
980:defined
874:PKCS#10
497:Windows
449:Firefox
299:OpenPGP
291:bridges
218:ed25519
187:TLS/SSL
146:Website
77: (
57: (
2870:16 May
2315:
1725:OPC UA
1684:
1668:S/MIME
1662:
1639:
1610:
1602:PKCS12
1084:
1045:
1027:PKCS#7
952:PKCS#7
938:PKCS#7
928:PKCS#7
918:S/MIME
914:PKCS#7
904:PKCS#7
848:PKCS#8
832:above)
797:Base64
699:
653:
638:
600:
475:
461:Chrome
457:Safari
388:cannot
344:, and
317:
295:meshes
177:is an
136:Domain
107:Series
41:Status
3300:X.500
2761:(PDF)
2712:(PDF)
2650:(PDF)
2643:(PDF)
2579:(PDF)
2531:(PDF)
2480:(PDF)
2407:(PDF)
2383:(PDF)
2362:(PDF)
2277:(PDF)
1994:(PDF)
1823:. ITU
1802:EdDSA
1678:IPsec
1656:HTTPS
1580:PKCS7
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