SB20260720281 - Out-of-bounds write in Linux kernel typec tcpm driver



SB20260720281 - Out-of-bounds write in Linux kernel typec tcpm driver

Published: July 20, 2026

Security Bulletin ID SB20260720281
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Physical access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Out-of-bounds write (CVE-ID: CVE-2026-63960)

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

CVSSv4: 5.1 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


The vulnerability allows an attacker with physical access to cause memory corruption.

The vulnerability exists due to an out-of-bounds write in wcove_read_rx_buffer() when processing a crafted USB Power Delivery frame from a connected port partner. An attacker with physical access can transmit a crafted 31-byte frame to cause memory corruption.

The issue occurs on the IRQ thread stack, and the final register read may write past the end of struct pd_message.


Remediation

Install update from vendor's website.