Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix missing iov bounds check in parse_posix_sids() In parse_posix_sids(), sidsbuf_end is calculated using the server-supplied out_len without being validated against the actual length of the received iov (iov_len). If a server provides an inflated out_len, sidsbuf_end will point past the end of the iov. This defeats the bounds guards in posix_info_sid_size(), allowing out-of-bounds reads into adjacent kernel memory. Fix this by rejecting responses where the calculated sidsbuf_end would exceed the received iov boundaries or cause pointer wraparound.
References5
- git.kernel.org/stable/c/2f8ed71aaaba3bc8b19cd9930cc62e63e142b299
- git.kernel.org/stable/c/b09d092eb24ad0110f16a9b7c1ed5d2a0c1733dc
- git.kernel.org/stable/c/b862996e5105be1293da9cdc85da77b76021c3bd
- git.kernel.org/stable/c/d91b9a3b2b38e5ac1b51e9e5b23fe53ad7b49644
- git.kernel.org/stable/c/eac6917a42899aad0617bbf04798c5dd946a1fe5
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 0% percentile: 42 · as of 11 November 2026
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