PT-2026-64478 · Linux · Linux

CVE-2026-64257 · Published 2026-07-25 · Updated 2026-07-25

NVD

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.

Related Identifiers

CVE-2026-64257

Affected Products

Linux

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2026-64257 · Security Note
• https://git.kernel.org/stable/c/8986c932905ea508d66da421eb2eb6e676ace1fe · Note
• https://git.kernel.org/stable/c/57cba95f0e97c6f6e45e6731da30aff091bd7460 · Note
• https://git.kernel.org/stable/c/36bfa52459e45c0d5b668de2f1c91f6dc5c67775 · Note
• https://git.kernel.org/stable/c/fdafa1e68dc75045b7b617e6e7d2854950804d83 · Note
• https://git.kernel.org/stable/c/4a9d2657d3e05f6ed09c148cb127b4e58702275f · Note
• https://git.kernel.org/stable/c/445ece263131780dee273d727a4d6f11934feec7 · Note