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Certificate Transparency Search APIv1

Overview

When a publicly-trusted SSL certificate is issued, the event is recorded in multiple Certificate Transparency logs in the form of a certificate, a precertificate, or both. SSLMate monitors public Certificate Transparency logs, coalescing all the certificates and precertificates for a particular issuance event into a single issuance object. SSLMate indexes the issuances by DNS name, and you can use the API described below to efficiently query all the issuances for a particular domain, and then poll for new issuances. Learn more

List Issuances for a Domain

Use this endpoint to list all certificate issuances for a domain.

GET https://api.certspotter.com/v1/issuances?domain=DOMAIN

The following parameters may be specified in the query string:

domain

Return issuances that are valid for the given DNS name, which must be a registered domain or subordinate to a registered domain. For example, www.example.com and example.com are valid, but com is not.

DNS subject alternative names (SANs) and the subject common name (CN) are searched.

include_subdomains If true, also return issuances that are valid for sub-domains (of any depth) of domain. Default: false.
match_wildcards If true, also return issuances for wildcard DNS names that match domain. For example, a request for domain=www.example.com&match_wildcards=true will return issuances for *.example.com. Default: false.
after

Return issuances that were discovered by SSLMate after the issuance with the specified ID.

If the after parameter is empty or omitted, the API will return the least-recently-discovered issuances for the domain. To retrieve more-recently-discovered issuances, take the id field of the last issuance and pass it to the after parameter of your next query. Repeat until an empty response is returned.

expand Include the given field in the response, as described below. Repeat this parameter to expand multiple fields.

Response: JSON array of issuance objects, in the order that they were discovered by SSLMate.

Issuance Firehose

Use this endpoint to access a real-time stream of all certificate issuances as they are recorded in Certificate Transparency logs. Requires a subscription to Firehose Access.

GET https://api.certspotter.com/v1/issuances/firehose

The following parameters may be specified in the query string:

after

Return issuances that were discovered by SSLMate after the issuance with the specified ID.

If the after parameter is empty or omitted, the API will return issuances have been discovered in approximately the last hour. To retrieve additional issuances, take the id field of the last issuance and pass it to the after parameter of your next query. Repeat until an empty response is returned.

expand Include the given field in the response, as described below. Repeat this parameter to expand multiple fields.

Response: JSON array of issuance objects, in the order that they were discovered by SSLMate.

Issuance Object

An issuance is represented by a JSON object with the following fields:

id string An opaque string which uniquely identifies this issuance object.
tbs_sha256 string The hex-encoded SHA-256 digest of the TBSCertificate, as defined in RFC 6962 Section 3.2. The tbs_sha256 uniquely identifies this issuance.
cert_sha256 string The hex-encoded SHA-256 digest (sometimes called fingerprint) of the certificate (if known) or precertificate (if certificate not known). The digest is computed over the ASN.1 DER encoding.
dns_names array of strings DNS names for which the certificate is valid, taken from both the DNS subject alternative names (SANs) and the subject common name (CN). Internationalized domain names are encoded in Punycode. Only present if expanded.
pubkey_sha256 string The hex-encoded SHA-256 digest of the Subject Public Key Info.
issuer issuer object Information about the certificate authority which issued the certificate. Only present if expanded.
not_before string The not before time, in RFC 3339 format (e.g. 2016-06-16T00:00:00Z). This is usually the approximate time the certificate was issued, but certificate authorities often predate certificates so be careful when relying on this value.
not_after string The not after (expiration) time, in RFC 3339 format (e.g. 2016-06-16T00:00:00Z).
revoked nullable bool Indicates if the certificate is revoked. In rare cases, this field is null if the revocation status is unknown.
revocation revocation object Additional details about the issuance's revocation status. Only present if expanded.
problem_reporting nullable string Instructions on how to request the certificate be revoked. In rare cases, this field is null if SSLMate does not have instructions. Only present if expanded.
cert_der string The base64 representation of the DER-encoded X.509 certificate (if known) or precertificate (if certificate is not known). Only present if expanded.
cert object
Deprecated, use cert_der and cert_sha256 instead (click to show details)

Information about the certificate (if known) or precertificate (if certificate not known) corresponding to this issuance. Only present if expanded.

The sub-object has the following fields:

type string cert or precert. This field should generally be ignored. Do not treat certificates and precertificates differently unless you know what you are doing.
sha256 string The hex-encoded SHA-256 digest of the DER-encoded X.509 (pre)certificate. Use cert_sha256 from the issuance object instead.
data string The base64 representation of the DER-encoded X.509 (pre)certificate. Use cert_der from the issuance object instead.

Issuer Object

A certificate issuer is represented by a JSON object with the following fields:

friendly_name string The organization which issued the certificate. This name is curated by SSLMate to be an accurate and helpful way to identify the issuer of a certificate, so we recommend you use it instead of the certificate's Issuer Distinguished Name, which is often misleading, incorrect, or unhelpful. Note that friendly_name is intended for human consumption, and may change over time due to rebranding, mergers, or acquisitions; if you need a long-term identifier to programmatically compare against a list of authorized issuers, use caa_domains instead.
website nullable string The URL of the issuer's website, or null if unknown. Only present if expanded.
caa_domains nullable array of strings The domain names which can be placed in a CAA record to authorize the issuer. In rare cases, this field is null if SSLMate does not know this information. You can compare this field against the CAA records for your domain to determine if a certificate is authorized: at least one of the values in caa_domains should be in your domain's CAA record set. Only present if expanded.
operator nullable object

Information about the organization which controls the issuer's private key. In rare cases, this field is null if SSLMate does not know who controls the private key. Operator information is typically only useful to WebPKI security researchers. Only present if expanded.

The sub-object has the following fields:

name string The name of the organization.
website nullable string The URL of the organization's website, or null if unknown.
pubkey_sha256 string The hex-encoded SHA-256 digest of the issuer's DER-encoded Subject Public Key Info.
pubkey_der string The base64 representation of the issuer's DER-encoded Subject Public Key Info. Only present if expanded.
name string The distinguished name of the issuer, formatted according to RFC 2253. This field is controlled by the certificate authority and often contains misleading, incorrect, or unhelpful information, so you should use friendly_name instead unless you are concerned with PKI minutiae.
name_der string The base64 representation of the issuer's DER-encoded distinguished name. This field is only useful if you are concerned with PKI minutiae. Only present if expanded.

Revocation Object

Revocation details are contained in a JSON object with the following fields:

time nullable string The time of the revocation, in RFC 3339 format. null if the certificate is not revoked or if the revocation status is unknown.
reason nullable integer The RFC 5280 reason code explaining why the certificate was revoked. See Mozilla's Revocation Reasons documentation for information about the meaning of each reason code. Be aware that certificate authorities do not always provide an accurate reason so the utility of this field may be limited. This field is null if the certificate is not revoked or if the revocation status is unknown.
checked_at nullable string The time at which SSLMate checked the certificate's revocation status, in RFC 3339 format. null if the revocation status is unknown.

Revocation status is unknown in the following cases:

  • The certificate is expired. Expired certificates are not trusted anyways, so revocation is inapplicable.
  • The certificate is so malformed that its revocation status can't be checked. Most certificate consumers will reject the certificate.
  • The certificate issuer doesn't publish valid certificate revocation lists (CRLs). Note that all SSL certificate authorities trusted by Mozilla and Apple are required to publish valid CRLs. SSLMate monitors CAs for compliance with this requirement and reports non-compliant CAs, so this case should be rare.

Example Issuance (with all non-deprecated fields expanded)

{ "id":"4326219514", "tbs_sha256":"db7c55f74732269c45fda91264003b2a25adc7ff2df687252f60772850449926", "cert_sha256":"20cbc0d1e87ed1d71d3b84533667ef60f22fffee634108711376dec87a38d4e2", "dns_names":["certs.sandbox.sslmate.com","certs.sslmate.com","sandbox.sslmate.com","sslmate.com","www.sslmate.com"], "pubkey_sha256":"1b1cebcd061ba39746a477db7b90d6871d648bd293ef50e053a6c54c5c3ac112", "issuer":{ "friendly_name":"Sectigo", "website":"https://sectigo.com/", "caa_domains":["sectigo.com","comodo.com","comodoca.com","usertrust.com","trust-provider.com"], "operator":{"name":"Sectigo","website":"https://sectigo.com/"}, "pubkey_sha256":"e1ae9c3de848ece1ba72e0d991ae4d0d9ec547c6bad1dddab9d6beb0a7e0e0d8", "pubkey_der":"MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA1nMz1tc8INAA0hdFuNY+B6I/x0HuMjDJsGz99J/LEpgPLT+NTQEMgg8Xf2Iu6bhIefsWg06t1zIlk7cHv7lQP6lMw0Aq6Tn/2YHKHxYyQdqAJrkjeocgHuP/IJo8lURvh3UGkEC0MpMWCRAIIz7S3YcPb11RFGoKacVPAXJpz9OTTG0EoKMbgn6xmrntxZ7FN3ifmgg0+1YuWMQJDgZkW7w33PGfKGioVrCSo1yfu4iYCBskHaswha6vsC6eep3BwEIc4gLw6uBK0u+QDrTBQBbwb4VCSmT3pDCg/r8uoydajotYuK3DGReEY+1vVv2Dy2A0xHS+5p3b4eTlygxfFQIDAQAB", "name":"C=GB, ST=Greater Manchester, L=Salford, O=Sectigo Limited, CN=Sectigo RSA Domain Validation Secure Server CA", "name_der":"MIGPMQswCQYDVQQGEwJHQjEbMBkGA1UECBMSR3JlYXRlciBNYW5jaGVzdGVyMRAwDgYDVQQHEwdTYWxmb3JkMRgwFgYDVQQKEw9TZWN0aWdvIExpbWl0ZWQxNzA1BgNVBAMTLlNlY3RpZ28gUlNBIERvbWFpbiBWYWxpZGF0aW9uIFNlY3VyZSBTZXJ2ZXIgQ0E=" }, "not_before":"2022-10-22T00:00:00Z", "not_after":"2023-11-21T23:59:59Z", "revoked":false, "revocation":{"time":null,"reason":null,"checked_at":"2022-12-19T18:47:39Z"}, "problem_reporting":"To revoke one or more certificates issued by Sectigo for which you (i) are the Subscriber or (ii) control the domain or (iii) have in your possession the private key, you may use our automated Revocation Portal here:\u000A ?? https://secure.sectigo.com/products/RevocationPortal\u000A\u000ATo programatically revoke one or more certificates issued by Sectigo for which you have in your possession the private key, you may use the ACME revokeCert method at this endpoint:\u000A ?? ACME Directory: https://acme.sectigo.com/v2/keyCompromise\u000A ?? revokeCert API: https://acme.sectigo.com/v2/keyCompromise/revokeCert\u000A\u000ATo report any other abuse, fraudulent, or malicious use of Certificates issued by Sectigo, please send email to:\u000A ?? For Code Signing Certificates: signedmalwarealert[at]sectigo[dot]com\u000A ?? For Other Certificates (SSL/TLS, S/MIME, etc): sslabuse[at]sectigo[dot]com", "cert_der":"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" }

Expanding Object Fields

As indicated in the documentation for an object, certain object fields are not included in responses by default. To include such a field, you must specify the field name in the request's expand parameter. This parameter can be specified more than once to expand multiple fields.

To expand a field that is nested in another field, specify the parent field name, a dot (.), and the child field name. For example, specify issuer.caa_domains to expand the caa_domains field of the issuer field.

Example: GET https://api.certspotter.com/v1/issuances?domain=example.com&expand=dns_names&expand=issuer&expand=issuer.caa_domains

Issuance Pagination

The API returns a limited number of issuances in a single response. To retrieve additional issuances, take the id field of the last issuance and pass it to the issuances endpoint in the after parameter (leaving the other parameters as-is). Repeat until the issuances endpoint returns an empty array.

Polling For New Issuances

When the issuances endpoint returns an empty array, it includes a Retry-After HTTP header containing a number of seconds. After the specified time has elapsed, you may retry the request. If SSLMate has discovered new issuances matching your query, they will be returned. You can then request subsequent pages until another empty response is returned.

Authentication

You can make a limited number of unauthenticated API queries per hour, for personal or evaluation purposes.

When you're ready to launch in production, we ask that you sign up for an account and authenticate to the API using one the following methods:

Examples:

curl -H "Authorization: Bearer 123_sampleapikey" https://api.certspotter.com/v1/issuances?domain=example.com

curl -u 123_sampleapikey: https://api.certspotter.com/v1/issuances?domain=example.com

Provisioned Indexes

Provisioned indexes speed up full-domain queries of domains which have a large number of certificates. Provisioned indexes start at $100/month per domain. Contact us to set up a provisioned index.

Compatibility

SSLMate may make backwards-compatible changes to this API, such as adding new endpoints, adding new fields to responses, or adding new optional parameters to requests.

Backwards-incompatible changes will be avoided if at all possible, but should such a change become necessary, SSLMate will strive to provide at least 12 months notice. To ensure you receive notice, please use your API key when making requests.

See Also

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