CVE-2026-64257
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.66%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- EPSS
- 0.66% probability · 50th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/36bfa52459e45c0d5b668de2f1c91f6dc5c67775Patch
- https://git.kernel.org/stable/c/445ece263131780dee273d727a4d6f11934feec7Patch
- https://git.kernel.org/stable/c/4a9d2657d3e05f6ed09c148cb127b4e58702275fPatch
- https://git.kernel.org/stable/c/57cba95f0e97c6f6e45e6731da30aff091bd7460Patch
- https://git.kernel.org/stable/c/8986c932905ea508d66da421eb2eb6e676ace1fePatch
- https://git.kernel.org/stable/c/fdafa1e68dc75045b7b617e6e7d2854950804d83Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.