--- id: CVE-2026-63074 title: |- Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid) summary: |- Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a server reuses an OSSL_CMP_CTX frequentl… 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' - url: 'https://access.redhat.com/errata/RHSA-2026:71603' tags: - nvd - csaf - vex - red-hat epss: 0.0056 epssPercentile: 0.4426 ingestedAt: '2026-09-12T00:03:49.031Z' scores: nvd: 5.9 vendor: 7.5 --- ## Overview Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory growth in the event a malicious client repeatedly sends requests containing unique extra certificates, which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends messages intending to be rejected with a large list of additional certificates repeatedly, forcing the server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is rejected, using the same method as when the context is configured to not do caching at all. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE. ## 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` ## Remediation Upgrade past the affected range: - `openssl 4.0.2` ## Vendor advisories - **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) - **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) - **RHSA-2026:59641** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-08-25 · [advisory](https://access.redhat.com/errata/RHSA-2026:59641) - **RHSA-2026:59635** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-08-25 · [advisory](https://access.redhat.com/errata/RHSA-2026:59635) - **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 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63074.json) - **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) - **RHSA-2026:71603** · Red Hat · fixed in: Red Hat Update Infrastructure 5 · released 2026-09-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:71603)