Description
In the Linux kernel, the following vulnerability has been resolved: fs/smb/client: fix out-of-bounds read in cifs_sanitize_prepath When cifs_sanitize_prepath is called with an empty string or a string containing only delimiters (e.g., "/"), the current logic attempts to check *(cursor2 - 1) before cursor2 has advanced. This results in an out-of-bounds read. This patch adds an early exit check after stripping prepended delimiters. If no path content remains, the function returns NULL. The bug was identified via manual audit and verified using a standalone test case compiled with AddressSanitizer, which triggered a SEGV on affected inputs.
Affected products
linux: linux kernel
References10
- git.kernel.org/stable/c/2d29214448ec0f4e7e18bb1c14dd4a6c07f1c439 Patch
- git.kernel.org/stable/c/49b1ce6d7cfb6c5a49f68bf5ccfcfb6ba14e63c3 Patch
- git.kernel.org/stable/c/5d4fe469fe7dbff7d874c196bb680a82f2625d95 Patch
- git.kernel.org/stable/c/78ec5bf2f589ec7fd8f169394bfeca541b077317 Patch
- git.kernel.org/stable/c/86f9c23e0814cfdffda9eedf0c591c51ba209010 Patch
- git.kernel.org/stable/c/a2ba20c17de8eb028f96b1d85f119d3d25655bd9
- git.kernel.org/stable/c/fbced33599653471b4581dfe1abc7b467031f126
- access.redhat.com/errata/RHSA-2026:34911
- access.redhat.com/errata/RHSA-2026:36018
- access.redhat.com/errata/RHSA-2026:36365
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 29 · as of 13 November 2026
- CWE
- CWE-125
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