CVE-2025-21640

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Source
https://cve.org/CVERecord?id=CVE-2025-21640
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21640.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2025-21640
Downstream
Related
Published
2025-01-19T10:17:57.593Z
Modified
2026-03-20T12:40:37.411233Z
Summary
sctp: sysctl: cookie_hmac_alg: avoid using current->nsproxy
Details

In the Linux kernel, the following vulnerability has been resolved:

sctp: sysctl: cookiehmacalg: 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.sctphmacalg' is used.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21640.json",
    "cna_assigner": "Linux"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
3c68198e75111a905ac2412be12bf7b29099729b
Fixed
5599b212d2f4466e1832a94e9932684aaa364587
Fixed
03ca51faba2b017bf6c90e139434c4117d0afcdc
Fixed
86ddf8118123cb58a0fb8724cad6979c4069065b
Fixed
3cd0659deb9c03535fd61839e91d4d4d3e51ac71
Fixed
ad673e514b2793b8d5902f6ba6ab7e890dea23d5
Fixed
f0bb3935470684306e4e04793a20ac4c4b08de0b
Fixed
ea62dd1383913b5999f3d16ae99d411f41b528d4

Database specific

source 
"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21640.json"