{"id":"CVE-2025-27370","aliases":["EUVD-2025-5571","GHSA-pcj4-9fcj-56c8"],"status":"published","title":"OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations....","description":"OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations. When the private_key_jwt authentication mechanism is used, a malicious Authorization Server could trick a Client into writing attacker-controlled values into the audience, including token endpoints or issuer identifiers of other Authorization Servers. The malicious Authorization Server could then use these private key JWTs to impersonate the Client.","severity":{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:H/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00345,"percentile":0.28471,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-305","CWE-863"],"published":"2025-03-03T00:00:00Z","modified":"2026-06-17T09:03:28Z","products":[{"vendor":"openid","product":"openid connect"}],"references":[{"url":"https://openid.net/wp-content/uploads/2025/01/OIDF-Responsible-Disclosure-Notice-on-Security-Vulnerability-for-private_key_jwt.pdf"},{"url":"https://openid.net/notice-of-a-security-vulnerability/"},{"url":"https://talks.secworkshop.events/osw2025/talk/R8D9BS/"},{"url":"https://github.com/OWASP/ASVS/issues/2678"},{"url":"https://eprint.iacr.org/2025/629"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-27370"},{"url":"https://openid.net/notice-of-a-security-vulnerability"},{"url":"https://talks.secworkshop.events/osw2025/talk/R8D9BS"},{"url":"https://github.com/advisories/GHSA-pcj4-9fcj-56c8"}],"sources":{"cve":[{"id":"CVE-2025-27370","description":"OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations. When the private_key_jwt authentication mechanism is used, a malicious Authorization Server could trick a Client into writing attacker-controlled values into the audience, including token endpoints or issuer identifiers of other Authorization Servers. The malicious Authorization Server could then use these private key JWTs to impersonate the Client.","status":"published","published":"2025-03-03T00:00:00Z","modified":"2025-04-25T14:43:40.581Z","cvss":[{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:H/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-305"],"updated_at":"2026-11-02T14:32:42.078906Z"}],"euvd":[{"id":"EUVD-2025-5571","description":"OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations. When the private_key_jwt authentication mechanism is used, a malicious Authorization Server could trick a Client into writing attacker-controlled values into the audience, including token endpoints or issuer identifiers of other Authorization Servers. The malicious Authorization Server could then use these private key JWTs to impersonate the Client.","status":"published","published":"2025-03-03T00:00:00Z","modified":"2025-04-25T14:43:40Z","cvss":[{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:H/A:N","level":"medium"}],"updated_at":"2026-11-02T20:52:03.523577Z"}],"ghsa":[{"id":"GHSA-pcj4-9fcj-56c8","title":"OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations....","description":"OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations. When the private_key_jwt authentication mechanism is used, a malicious Authorization Server could trick a Client into writing attacker-controlled values into the audience, including token endpoints or issuer identifiers of other Authorization Servers. The malicious Authorization Server could then use these private key JWTs to impersonate the Client.","status":"published","published":"2025-03-03T18:31:29Z","modified":"2025-04-25T15:32:30Z","cvss":[{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:H/A:N","level":"medium"}],"cwes":["CWE-305","CWE-863"],"updated_at":"2026-11-02T15:02:02.261137Z"}],"nvd":[{"id":"CVE-2025-27370","description":"OpenID Connect Core through 1.0 errata set 2 allows audience injection in certain situations. When the private_key_jwt authentication mechanism is used, a malicious Authorization Server could trick a Client into writing attacker-controlled values into the audience, including token endpoints or issuer identifiers of other Authorization Servers. The malicious Authorization Server could then use these private key JWTs to impersonate the Client.","status":"published","published":"2025-03-03T18:15:40.65Z","modified":"2026-06-17T09:03:28.727Z","cvss":[{"version":"3.1","score":6.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:H/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-305"],"updated_at":"2026-11-02T14:10:52.398004Z"}]}}