Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: harden POSIX SID length parsing posix_info_sid_size() reads sid[1] to obtain the subauthority count, but its existing boundary check still accepts buffers with only one remaining byte. Require two bytes before reading sid[1] so all client paths that reuse the helper reject truncated POSIX SIDs safely.
Affected products
linux: linux kernel
References8
- git.kernel.org/stable/c/0de5b8e76847f5de26f364a82c6602c4881c30da Patch
- git.kernel.org/stable/c/171605aed68380c2fa75dff9b3a1ed427c50065b Patch
- git.kernel.org/stable/c/4213c1208978483021d7d125c131de3985d38f61 Patch
- git.kernel.org/stable/c/427eb7eb46425fec845a43e861f3d6e2899cae59 Patch
- git.kernel.org/stable/c/46a84715a015cb48e1b9c219dc88c03d8a541ea4 Patch
- git.kernel.org/stable/c/7ad2bcf2441430bb2e918fb3ef9a90d775a6e422 Patch
- git.kernel.org/stable/c/86c5d470f5d42e61123b2f4b4f0b91f4eee5b980 Patch
- git.kernel.org/stable/c/96e889bc1e759c83f25093e8c2f3da31b4973f30 Patch
Metrics
- CVSS 3.1
-
8.2
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - EPSS — exploit probability
- 0% percentile: 39 · as of 14 November 2026
- CWE
- CWE-125
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