SB2026090438 - Out-of-bounds write in Linux kernel dev_validate_header in the network device header validation path



SB2026090438 - Out-of-bounds write in Linux kernel dev_validate_header in the network device header validation path

Published: September 4, 2026

Security Bulletin ID SB2026090438
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Data manipulation

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Out-of-bounds write (CVE-ID: CVE-2026-80731)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: 1.8 [CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N]


The vulnerability allows a local privileged user to cause memory corruption.

The vulnerability exists due to an out-of-bounds write in dev_validate_header when validating short link-layer headers after a network device's hard_header_len increases. A local privileged user can trigger zero-padding of a short link-layer header to cause memory corruption.

The affected path is limited to variable-length layer-2 protocols where the header length is at least min_header_len but shorter than hard_header_len.


Remediation

Install update from vendor's website.