{"id":"CVE-2026-75805","summary":"NULL Pointer Dereference in CMP Client Revocation Response Handling","details":"Issue summary: A CMP client that requests certificate revocation on the basis\nof a PKCS#10 CSR may dereference a NULL pointer and terminate abnormally when\nprocessing a crafted revocation response. \n\nImpact summary: The NULL pointer dereference happens on a read which \nleads to a crash and a Denial of Service for the affected client application.\n\nCWE: CWE-476: NULL-pointer dereference\n\nDescription: A CMP client revoking a certificate has to tell the server which\ncertificate to revoke, and may do so by supplying a PKCS#10 CSR instead of the\ncertificate itself or its issuer name and serial number. This is\n'openssl cmp -cmd rr -csr \u003cfile\u003e' on the command line, or\nOSSL_CMP_exec_RR_ses() with the certificate supplied via\nOSSL_CMP_CTX_set1_p10CSR() through the API.\n\nA CSR does not contain the issuer name and serial number of the certificate,\nso the client does not send them. A server may optionally name the\ncertificate it revoked in its response, and the client then compares that\nname against what it sent. Having sent neither an issuer name nor a serial\nnumber, it has nothing to compare against, and a server returning a specially\ncrafted name causes the client to read from a NULL pointer and crash.\n\nThe revocation response is checked for valid message protection before\nthe affected code is reached, so an attacker must be a malicious or\ncompromised CMP server, or a man-in-the-middle in possession of the\nsecret used for message protection. Clients that identify the certificate\nto be revoked by a certificate or by issuer and serial number rather\nthan by a PKCS#10 CSR are not affected.\n\nFIPS impact: no\nNo FIPS modules are affected by this issue, as the CMP protocol\nimplementation is outside the OpenSSL FIPS module boundary.","modified":"2026-09-30T03:49:55.144684516Z","published":"2026-09-29T15:32:20.408Z","database_specific":{"cwe_ids":["CWE-476"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75805.json","unresolved_ranges":[{"extracted_events":[{"introduced":"3.0.0"},{"fixed":"3.0.23"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"openssl"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75805.json"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/7588db7fef14209c3caa3a101d11a02006b19166"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/7ca0ccb5172a577e9b87267d77bfe21e5481a5e7"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/9eb2a8a9b86136cdb39d6d7d50644dd66941cdc3"},{"type":"FIX","url":"https://github.com/openssl/openssl/commit/abf02872a4b71767ecc72293424420f5b009190f"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-75805"},{"type":"ADVISORY","url":"https://openssl-library.org/news/secadv/20260929.txt"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/openssl/openssl","events":[{"introduced":"11b7b6ea3b65a584e1d31408ed1bdb139465cffd"},{"fixed":"af1775b60dfa141a4ad762585052cabeb9f37e9e"},{"introduced":"7b371d80d959ec9ab4139d09d78e83c090de9779"},{"fixed":"c8bd5a57108599ac650bbae77fcabe3109dab2e8"},{"introduced":"636dfadc70ce26f2473870570bfd9ec352806b1d"},{"fixed":"45e844fa2a14ec92d146bd8f5778ac130b6625fb"},{"introduced":"98acb6b02839c609ef5b837794e08d906d965335"},{"fixed":"e72c946f6f6d94c8ba5119acb25340b7b6b2073f"}],"database_specific":{"extracted_events":[{"introduced":"4.0.0"},{"fixed":"4.0.3"},{"introduced":"3.6.0"},{"fixed":"3.6.5"},{"introduced":"3.5.0"},{"fixed":"3.5.9"},{"introduced":"3.4.0"},{"fixed":"3.4.8"}],"source":"AFFECTED_FIELD"}}],"versions":["openssl-3.4.7","openssl-3.5.8","openssl-3.6.4","openssl-4.0.2","openssl-3.4.6","openssl-3.5.7","openssl-3.6.3","openssl-4.0.1","openssl-4.0.0","openssl-3.4.5","openssl-3.5.6","openssl-3.6.2","openssl-3.4.4","openssl-3.5.5","openssl-3.6.1","3.4-POST-CLANG-FORMAT-WEBKIT","3.4-PRE-CLANG-FORMAT-WEBKIT","3.5-POST-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-3.4.3","openssl-3.5.4","openssl-3.5.3","openssl-3.5.2","openssl-3.4.2","openssl-3.5.1","openssl-3.5.0","openssl-3.4.1","openssl-3.4.0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-75805.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"}]}