SB20260720267 - Improper input validation in Linux kernel typec ucsi driver



SB20260720267 - Improper input validation in Linux kernel typec ucsi driver

Published: July 20, 2026

Security Bulletin ID SB20260720267
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 input validation (CVE-ID: CVE-2026-63964)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


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

The vulnerability exists due to improper input validation in the do_flash() function in the ucsi_ccg driver when parsing a crafted firmware image without a ':' record header. A local privileged user can place a crafted firmware file under /lib/firmware and write to the do_flash sysfs attribute to cause a denial of service.

The issue can be triggered by an unsigned firmware blob reaching the flashing logic.


Remediation

Install update from vendor's website.