{"id":"CVE-2026-63076","summary":"Invalid Pointer Dereference in CMP Server via Crafted protectionAlg","details":"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.","modified":"2026-08-30T08:17:27.162707Z","published":"2026-08-25T13:00:11.218Z","related":["openSUSE-SU-2026:11623-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63076.json","cna_assigner":"openssl","cwe_ids":["CWE-476"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63076.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63076"},{"type":"ADVISORY","url":"https://openssl-library.org/news/secadv/20260825.txt"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/37882aa2e0256e1072442a8f62f7db45b995c45b"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/a17cc8d612ecff6d94a9b7ca8b5283ddf5ff570e"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/a1f348ccb328c3afbd4ba6883f9b7c813c043259"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/a7af46a92d0ce19a90e669ef56d2576a07924226"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/cdacfff557389abfa9e4615abded2ec984517d6c"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/openssl/openssl","events":[{"introduced":"11b7b6ea3b65a584e1d31408ed1bdb139465cffd"},{"introduced":"7b371d80d959ec9ab4139d09d78e83c090de9779"},{"introduced":"636dfadc70ce26f2473870570bfd9ec352806b1d"},{"introduced":"98acb6b02839c609ef5b837794e08d906d965335"},{"introduced":"89cd17a031e022211684eb7eb41190cf1910f9fa"},{"fixed":"f089acdf4bc7ba94a79f4bf6eb7362c3e7d14aa9"},{"fixed":"d3c1b1169b3569ff3069e5b399f47b2b28e03d79"},{"fixed":"f4dc4d58b48d346a8270183f89acf826d459b0ca"},{"fixed":"0c5d912057abf47505b4ad455da49fbab99b76f1"},{"fixed":"a279090b9cd6b682a5a178410765a63e619fa2d9"},{"fixed":"37882aa2e0256e1072442a8f62f7db45b995c45b"},{"fixed":"a17cc8d612ecff6d94a9b7ca8b5283ddf5ff570e"},{"fixed":"a1f348ccb328c3afbd4ba6883f9b7c813c043259"}],"database_specific":{"extracted_events":[{"introduced":"4.0.0"},{"fixed":"4.0.2"},{"introduced":"3.6.0"},{"fixed":"3.6.4"},{"introduced":"3.5.0"},{"fixed":"3.5.8"},{"introduced":"3.4.0"},{"fixed":"3.4.7"},{"introduced":"3.0.0"},{"fixed":"3.0.22"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["openssl-3.0.21","openssl-3.4.6","openssl-3.5.7","openssl-3.6.3","openssl-4.0.1","openssl-4.0.0","openssl-3.0.20","openssl-3.4.5","openssl-3.5.6","openssl-3.6.2","openssl-3.0.19","openssl-3.4.4","openssl-3.5.5","openssl-3.6.1","3.4-POST-CLANG-FORMAT-WEBKIT","3.0-POST-CLANG-FORMAT-WEBKIT","3.4-PRE-CLANG-FORMAT-WEBKIT","3.5-POST-CLANG-FORMAT-WEBKIT","3.0-PRE-CLANG-FORMAT-WEBKIT","3.5-PRE-CLANG-FORMAT-WEBKIT","3.6-POST-CLANG-FORMAT-WEBKIT","3.6-PRE-CLANG-FORMAT-WEBKIT","openssl-3.6.0","openssl-3.0.18","openssl-3.4.3","openssl-3.5.4","openssl-3.5.3","openssl-3.5.2","openssl-3.0.17","openssl-3.4.2","openssl-3.5.1","openssl-3.5.0","openssl-3.0.16","openssl-3.4.1","openssl-3.4.0","openssl-3.0.15","openssl-3.0.14","openssl-3.0.13","openssl-3.0.12","openssl-3.0.11","openssl-3.0.10","openssl-3.0.9","openssl-3.0.8","openssl-3.0.7","openssl-3.0.6","openssl-3.0.5","openssl-3.0.4","openssl-3.0.3","openssl-3.0.2","openssl-3.0.1","openssl-3.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63076.json","vanir_signatures_modified":"2026-08-30T08:17:27Z","vanir_signatures":[{"digest":{"function_hash":"106587459071139848616027292385591674687","length":2226},"id":"CVE-2026-63076-6da1632b","signature_type":"Function","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/a1f348ccb328c3afbd4ba6883f9b7c813c043259","target":{"file":"crypto/cmp/cmp_protect.c","function":"ossl_cmp_calc_protection"},"deprecated":false},{"digest":{"line_hashes":["89468342301851265665889764551945748234","154015450110099968683859733324895660673","99937134846491295684936526173010685312","69426374678207311866996959622545977209"],"threshold":0.9},"id":"CVE-2026-63076-81bd0ce4","signature_type":"Line","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/a17cc8d612ecff6d94a9b7ca8b5283ddf5ff570e","target":{"file":"crypto/cmp/cmp_protect.c"},"deprecated":false},{"id":"CVE-2026-63076-a910a821","signature_type":"Line","signature_version":"v1","source":"https://github.com/openssl/openssl/commit/37882aa2e0256e1072442a8f62f7db45b995c45b","target":{"file":"crypto/cmp/cmp_protect.c"},"deprecated":false,"digest":{"line_hashes":["89468342301851265665889764551945748234","154015450110099968683859733324895660673","99937134846491295684936526173010685312","69426374678207311866996959622545977209"],"threshold":0.9}},{"source":"https://github.com/openssl/openssl/commit/37882aa2e0256e1072442a8f62f7db45b995c45b","target":{"file":"crypto/cmp/cmp_protect.c","function":"ossl_cmp_calc_protection"},"deprecated":false,"digest":{"function_hash":"66919414319172588973685798552640721673","length":2312},"id":"CVE-2026-63076-bacf5626","signature_type":"Function","signature_version":"v1"},{"signature_type"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