High 7.1Published Jan 19, 2025

CVE-2025-21640sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy

Updated under an hour ago (Oct 26, 2026, 9:40 PM ET)

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Exploited in the last 30 days

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.

CVSS: 7.1 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 15, 2026
First seen by InfoSec Signals: Oct 14, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 3c68198e75111a905ac2412be12bf7b29099729b before 5599b212d2f4466e1832a94e9932684aaa364587; from 3c68198e75111a905ac2412be12bf7b29099729b before 03ca51faba2b017bf6c90e139434c4117d0afcdc; from 3c68198e75111a905ac2412be12bf7b29099729b before 86ddf8118123cb58a0fb8724cad6979c4069065b; from 3c68198e75111a905ac2412be12bf7b29099729b before 3cd0659deb9c03535fd61839e91d4d4d3e51ac71; from 3c68198e75111a905ac2412be12bf7b29099729b before ad673e514b2793b8d5902f6ba6ab7e890dea23d5; from 3c68198e75111a905ac2412be12bf7b29099729b before f0bb3935470684306e4e04793a20ac4c4b08de0b; from 3c68198e75111a905ac2412be12bf7b29099729b before ea62dd1383913b5999f3d16ae99d411f41b528d4	CNA record
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem siemens:simatic_s7_1500_tm_mfp_gnu_linux_subsystem (from the name)	all versions	CISA ADP
linux linux_kernel linux:linux_kernel	from 3.8 before 6.1.125; from 6.2 before 6.6.72; from 6.7 before 6.12.10; 6.13; 6.13; 6.13; 6.13; 6.13; and 1 more ranges	NVD

References

References

https://git.kernel.org/stable/c/5599b212d2f4466e1832a94e9932684aaa364587
https://git.kernel.org/stable/c/03ca51faba2b017bf6c90e139434c4117d0afcdc	patch
https://git.kernel.org/stable/c/86ddf8118123cb58a0fb8724cad6979c4069065b	patch
https://git.kernel.org/stable/c/3cd0659deb9c03535fd61839e91d4d4d3e51ac71	patch
https://git.kernel.org/stable/c/ad673e514b2793b8d5902f6ba6ab7e890dea23d5	patch
https://git.kernel.org/stable/c/f0bb3935470684306e4e04793a20ac4c4b08de0b	patch
https://git.kernel.org/stable/c/ea62dd1383913b5999f3d16ae99d411f41b528d4	patch
https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html
https://cert-portal.siemens.com/productcert/html/ssa-265688.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.