SB20260816369 - Improper locking in Linux kernel mtd spi-nor driver



SB20260816369 - Improper locking in Linux kernel mtd spi-nor driver

Published: August 16, 2026

Security Bulletin ID SB20260816369
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Improper locking (CVE-ID: CVE-2026-72155)

CWE-ID: CWE-667 - Improper Locking

CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper lock state handling in the spi_nor_sr_unlock() function in the spi-nor software protection logic when processing unlock requests for locked blocks at the beginning of the device. A local user can request unlocking of the currently locked block or blocks to cause a denial of service.

The issue occurs when the first block, or a few first blocks, are locked and both top and bottom unlocking paths can achieve the same result.


Remediation

Install update from vendor's website.