High severity8.2NVD Advisory· Published Jul 25, 2026· Updated Sep 8, 2026
CVE-2026-64380
CVE-2026-64380
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
3- osv-coords2 versions
>= 5.7.0, < 5.10.261+ 1 more
- (no CPE)range: >= 5.7.0, < 5.10.261
- (no CPE)range: < 7.1.7-1.1
Patches
Vulnerability mechanics
References
8- git.kernel.org/stable/c/0de5b8e76847f5de26f364a82c6602c4881c30danvdPatch
- git.kernel.org/stable/c/171605aed68380c2fa75dff9b3a1ed427c50065bnvdPatch
- git.kernel.org/stable/c/4213c1208978483021d7d125c131de3985d38f61nvdPatch
- git.kernel.org/stable/c/427eb7eb46425fec845a43e861f3d6e2899cae59nvdPatch
- git.kernel.org/stable/c/46a84715a015cb48e1b9c219dc88c03d8a541ea4nvdPatch
- git.kernel.org/stable/c/7ad2bcf2441430bb2e918fb3ef9a90d775a6e422nvdPatch
- git.kernel.org/stable/c/86c5d470f5d42e61123b2f4b4f0b91f4eee5b980nvdPatch
- git.kernel.org/stable/c/96e889bc1e759c83f25093e8c2f3da31b4973f30nvdPatch
News mentions
1- Linux Kernel: 25 Vulnerabilities Across Subsystems Disclosed and Patched TogetherVypr Intelligence · Jul 26, 2026