{"id":"CVE-2026-63074","title":"Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches\nadditional certificates (extraCerts) sent in a CMP message, but never expunges\nthem (for instance if they are invalid)","summary":"Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches\nadditional certificates (extraCerts) sent in a CMP message, but never expunges\nthem (for instance if they are invalid).  If a server reuses an OSSL_CMP_CTX\nfrequentl…","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-770"],"vendor":"openssl","product":"openssl","affected":["openssl >= 3.0.0, < 3.0.22","openssl >= 3.4.0, < 3.4.7","openssl >= 3.5.0, < 3.5.8","openssl >= 3.6.0, < 3.6.4","openssl >= 4.0.0, < 4.0.2"],"patched":["openssl 4.0.2"],"published":"2026-08-25","updated":"2026-09-11","sourceUpdated":"2026-09-11T21:16:58.127","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-63074","references":[{"url":"https://github.com/openssl/openssl/commit/01e567978a55fba18142a230380c31296049fae7","label":"openssl-security@openssl.org"},{"url":"https://github.com/openssl/openssl/commit/21a5d9658b0c66daace60e10ea18ff32a448de9f","label":"openssl-security@openssl.org"},{"url":"https://github.com/openssl/openssl/commit/74ae7f6df47a5767c1010b88c47507dfc5b32c46","label":"openssl-security@openssl.org"},{"url":"https://github.com/openssl/openssl/commit/75360af9650d4e0c82ba0050c5c9912cd79e54af","label":"openssl-security@openssl.org"},{"url":"https://github.com/openssl/openssl/commit/f636f9ca0fa1bae5b42f9e787f025c96fb09c43a","label":"openssl-security@openssl.org"},{"url":"https://openssl-library.org/news/secadv/20260825.txt","label":"openssl-security@openssl.org"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63074.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-63074"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2517566"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-63074"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63074"},{"url":"https://access.redhat.com/errata/RHSA-2026:67154"},{"url":"https://access.redhat.com/errata/RHSA-2026:67165"},{"url":"https://access.redhat.com/errata/RHSA-2026:59641"},{"url":"https://access.redhat.com/errata/RHSA-2026:59635"},{"url":"https://access.redhat.com/errata/RHSA-2026:67956"}],"tags":["nvd","csaf","vex","red-hat"],"epss":0.00495,"epssPercentile":0.4156,"ingestedAt":"2026-09-12T00:03:49.031Z","scores":{"nvd":5.9,"vendor":7.5},"slug":"CVE-2026-63074","body":"## Overview\n\nIssue summary: The OpenSSL Certificate Management Protocol (CMP) caches\nadditional certificates (extraCerts) sent in a CMP message, but never expunges\nthem (for instance if they are invalid).  If a server reuses an OSSL_CMP_CTX\nfrequently, this cache of extraCerts may grow unboundedly, and a malicious\nclient may flood a CMP server with requests driving this growth.\n\nImpact summary: Users utilizing a CMP server that reuses a single OSSL_CMP_CTX\nfor the lifetime of a server process may observe unbounded memory growth in the\nevent a malicious client repeatedly sends requests containing unique extra\ncertificates, which may lead to OOM conditions.\n\nCWE: CWE-770: Allocation of Resources Without Limits or Throttling\n\nDescription: If a remote user sends CMP messages to a server with a list of\nextraCerts and the message is rejected, the extraCerts from the message remains\nin the server contexts untrusted certificate stack.  This exposes servers with\nlong lived ctx objects to Denial of Service attacks in which an attacker sends\nmessages intending to be rejected with a large list of additional certificates\nrepeatedly, forcing the server to store them indefinitely.\n   \nThe issue was fixed by removing the added extra certs if the message is\nrejected, using the same method as when the context is configured to not do\ncaching at all.\n\nFIPS impact: no\nAs the CMP code lives outside the FIPS module boundary, no FIPS\nmodules are affected by this CVE.\n\n## Affected\n\n- `openssl >= 3.0.0, < 3.0.22`\n- `openssl >= 3.4.0, < 3.4.7`\n- `openssl >= 3.5.0, < 3.5.8`\n- `openssl >= 3.6.0, < 3.6.4`\n- `openssl >= 4.0.0, < 4.0.2`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `openssl 4.0.2`\n\n## Vendor advisories\n\n- **RHSA-2026:67154** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67154)\n- **RHSA-2026:67165** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9) · released 2026-09-14 · [advisory](https://access.redhat.com/errata/RHSA-2026:67165)\n- **RHSA-2026:59641** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-08-25 · [advisory](https://access.redhat.com/errata/RHSA-2026:59641)\n- **RHSA-2026:59635** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-08-25 · [advisory](https://access.redhat.com/errata/RHSA-2026:59635)\n- **Red Hat VEX** · Low · affected: Red Hat Developer Hub, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat JBoss Core Services, Red Hat JBoss Web Server 6, Red Hat JBoss Web Server 7, … · no fix planned: Red Hat Developer Hub, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat JBoss Core Services, … · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63074.json)\n- **RHSA-2026:67956** · Red Hat · fixed in: Red Hat Update Infrastructure 5 · released 2026-09-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:67956)","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}