Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: reject overlapping data areas in SMB2 responses Commit 53b7c271f06b ("smb: client: restrict implied bcc[0] exemption to responses without data area") restricted the implied bcc[0] length exception to responses without a data area. However, the overlap handling in __smb2_calc_size() clears data_length, which can make an invalid response appear to have no data area and so qualify for the exception. Track data area overlap separately and reject such responses before applying the length compatibility exceptions.
Affected products
linux: linux kernel
References6
- git.kernel.org/stable/c/36bfa52459e45c0d5b668de2f1c91f6dc5c67775 Patch
- git.kernel.org/stable/c/445ece263131780dee273d727a4d6f11934feec7 Patch
- git.kernel.org/stable/c/4a9d2657d3e05f6ed09c148cb127b4e58702275f Patch
- git.kernel.org/stable/c/57cba95f0e97c6f6e45e6731da30aff091bd7460 Patch
- git.kernel.org/stable/c/8986c932905ea508d66da421eb2eb6e676ace1fe Patch
- git.kernel.org/stable/c/fdafa1e68dc75045b7b617e6e7d2854950804d83 Patch
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H - EPSS — exploit probability
- 1% percentile: 52 · as of 14 November 2026
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