{"id":"CVE-2026-75805","title":"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","summary":"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 dere…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","cwe":["CWE-476"],"vendor":"openssl","product":"openssl","affected":["openssl >= 3.0.0, < 3.0.23","openssl >= 3.4.0, < 3.4.8","openssl >= 3.5.0, < 3.5.9","openssl >= 3.6.0, < 3.6.5","openssl >= 4.0.0, < 4.0.3"],"patched":["openssl 4.0.3"],"published":"2026-09-29","updated":"2026-10-08","sourceUpdated":"2026-10-08T01:20:24.147","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-75805","references":[{"url":"https://github.com/openssl/openssl/commit/7588db7fef14209c3caa3a101d11a02006b19166","label":"openssl-security@openssl.org"},{"url":"https://github.com/openssl/openssl/commit/7ca0ccb5172a577e9b87267d77bfe21e5481a5e7","label":"openssl-security@openssl.org"},{"url":"https://github.com/openssl/openssl/commit/9eb2a8a9b86136cdb39d6d7d50644dd66941cdc3","label":"openssl-security@openssl.org"},{"url":"https://github.com/openssl/openssl/commit/abf02872a4b71767ecc72293424420f5b009190f","label":"openssl-security@openssl.org"},{"url":"https://openssl-library.org/news/secadv/20260929.txt","label":"openssl-security@openssl.org"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-75805.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-75805"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2543247"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-75805"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-75805"},{"url":"https://access.redhat.com/errata/RHSA-2026:74162"},{"url":"https://access.redhat.com/errata/RHSA-2026:74166"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00324,"epssPercentile":0.25337,"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-09-29T16:54:03.315064Z"},"scores":{"nvd":5.3,"vendor":5.9},"ingestedAt":"2026-09-29T16:39:33.267Z","slug":"CVE-2026-75805","body":"## Overview\n\nIssue 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 <file>' 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.\n\n## Affected\n\n- `openssl >= 3.0.0, < 3.0.23`\n- `openssl >= 3.4.0, < 3.4.8`\n- `openssl >= 3.5.0, < 3.5.9`\n- `openssl >= 3.6.0, < 3.6.5`\n- `openssl >= 4.0.0, < 4.0.3`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `openssl 4.0.3`\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4, Self-service automation portal 2 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4, Self-service automation portal 2 · updated 2026-10-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-75805.json)\n- **RHSA-2026:74162** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-30 · [advisory](https://access.redhat.com/errata/RHSA-2026:74162)\n- **RHSA-2026:74166** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-30 · [advisory](https://access.redhat.com/errata/RHSA-2026:74166)","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":212859,"id":"CVE-2026-75805","ts":1790703710855,"field":"cvss","old":null,"new":"5.3"},{"seq":212858,"id":"CVE-2026-75805","ts":1790703710855,"field":"severity","old":"none","new":"medium"}]}