Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV L L L N U N N H 5.5 .0024 14.9 —
AFFECTED Product Versions Fixed Linux 3c68198e75111a905ac2412be12bf7b29099729b – — Linux 3.8 – 5.4.292
TIMELINE Dec 29 Reserved by Linux Jan 19 Published (CNA: Linux) Jul 30 RESCORED — CVE-2025-21640 (Linux). CVSS 7.1 → 5.5 (NVD).
In the Linux kernel, the following vulnerability has been resolved: sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy As mentioned in a previous commit of this series, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'net' structure can be obtained from the table->data using container_of(). Note that table->data could also be used directly, as this is the only member needed from the 'net' structure, but that would increase the size of this fix, to use '*data' everywhere 'net->sctp.sctp_hmac_alg' is used.
| Date | Event | Detail |
|---|---|---|
| December 29, 2024 | Reserved | Reserved by Linux |
| January 19, 2025 | Published | Published (CNA: Linux) |
| July 30, 2026 | RESCORED | RESCORED — CVE-2025-21640 (Linux). CVSS 7.1 → 5.5 (NVD). |
Authoritative record: CVE-2025-21640 at cve.org
Vendors: linux
Weaknesses: CWE-476
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2025-21640 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.