{"attribution":"This product uses data from the NVD API but is not endorsed or certified by the NVD.","cve":{"id":"CVE-2026-63076","sourceIdentifier":"openssl-security@openssl.org","published":"2026-08-25T13:19:26.543","lastModified":"2026-09-11T21:17:12.460","vulnStatus":"Analyzed","cveTags":[],"descriptions":[{"lang":"en","value":"Issue summary: OpenSSL CMP password based protection verification only\nchecks whether the protectionAlg parameter was not NULL and not its\nASN.1 type, before treating it as a PBMParameter. A crafted message can\ncontain a parameter of a different type, which is then dereferenced as an\ninvalid pointer.\n\nImpact summary: A remote, unauthenticated attacker can crash an application\nacting as a CMP server that accepts PBM-protected messages, or a CMP client\ntalking to a malicious or intercepted CMP server, resulting in a Denial of\nService.\n\nCWE: CWE-476: NULL Pointer Dereference\n\nDescription: When verifying the password-based MAC protection of a CMP\nmessage, OpenSSL library reads the protectionAlg algorithm parameter with\nX509_ALGOR_get0(), which returns both the parameter type and its value\npointer. The value is then cast to an ASN1_STRING and treated as the\nexpected PBMParameter after only checking that pointer is not NULL. The\nparameter type returned by X509_ALGOR_get0() was never consulted.\n\nThis happens during protection verification, before any MAC is computed, so\nno knowledge of the PBM shared secret is required; the only precondition is\nthat PBM verification is reachable. On the server side this is reached from\nOSSL_CMP_SRV_process_request() for any application that stands up a CMP\nserver accepting PBM-protected messages, and on the client side from CMP\nresponse validation against a malicious or on-path (MITM) server. The\nreliable consequence is a denial of service; there is no memory disclosure,\nno controlled memory write, and no path to code execution. CMP is a\nspecialized feature that an application must explicitly enable.\n\nFIPS impact: no\nAs the CMP code lives outside the FIPS module boundary, no FIPS modules\nare affected by this CVE."}],"affected":[{"source":"openssl-security@openssl.org","affectedData":[{"vendor":"OpenSSL","product":"OpenSSL","defaultStatus":"unaffected","versions":[{"version":"4.0.0","lessThan":"4.0.2","versionType":"semver","status":"affected"},{"version":"3.6.0","lessThan":"3.6.4","versionType":"semver","status":"affected"},{"version":"3.5.0","lessThan":"3.5.8","versionType":"semver","status":"affected"},{"version":"3.4.0","lessThan":"3.4.7","versionType":"semver","status":"affected"},{"version":"3.0.0","lessThan":"3.0.22","versionType":"semver","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-08-25T14:37:28.943884Z","id":"CVE-2026-63076","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"openssl-security@openssl.org","type":"Secondary","description":[{"lang":"en","value":"CWE-476"}]}],"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*","versionStartIncluding":"3.0.0","versionEndExcluding":"3.0.22","matchCriteriaId":"5DAAFBD8-3DEE-4F6B-8D83-02966005168A"},{"vulnerable":true,"criteria":"cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*","versionStartIncluding":"3.4.0","versionEndExcluding":"3.4.7","matchCriteriaId":"216D6529-561A-4684-A886-50954FBEBFB2"},{"vulnerable":true,"criteria":"cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*","versionStartIncluding":"3.5.0","versionEndExcluding":"3.5.8","matchCriteriaId":"C5BB9E95-09B6-4163-B51C-D62B528A04DA"},{"vulnerable":true,"criteria":"cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*","versionStartIncluding":"3.6.0","versionEndExcluding":"3.6.4","matchCriteriaId":"B1416826-F2F1-4EA8-9FB2-A56B0DA923C1"},{"vulnerable":true,"criteria":"cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*","versionStartIncluding":"4.0.0","versionEndExcluding":"4.0.2","matchCriteriaId":"63B8F45B-E44F-481C-815D-AF9CA89C48F6"}]}]}],"references":[{"url":"https://github.com/openssl/openssl/commit/37882aa2e0256e1072442a8f62f7db45b995c45b","source":"openssl-security@openssl.org","tags":["Patch"]},{"url":"https://github.com/openssl/openssl/commit/a17cc8d612ecff6d94a9b7ca8b5283ddf5ff570e","source":"openssl-security@openssl.org","tags":["Patch"]},{"url":"https://github.com/openssl/openssl/commit/a1f348ccb328c3afbd4ba6883f9b7c813c043259","source":"openssl-security@openssl.org","tags":["Patch"]},{"url":"https://github.com/openssl/openssl/commit/a7af46a92d0ce19a90e669ef56d2576a07924226","source":"openssl-security@openssl.org","tags":["Patch"]},{"url":"https://github.com/openssl/openssl/commit/cdacfff557389abfa9e4615abded2ec984517d6c","source":"openssl-security@openssl.org","tags":["Patch"]},{"url":"https://openssl-library.org/news/secadv/20260825.txt","source":"openssl-security@openssl.org","tags":["Vendor Advisory"]}]}}