SB20260720265 - Out-of-bounds write in Linux kernel typec tcpm driver

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds write (CVE-ID: CVE-2026-63962)

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

CVSSv4: 7.2 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to overwrite adjacent memory.

The vulnerability exists due to an out-of-bounds write in svdm_consume_modes() when processing an unsolicited Discover Modes ACK containing crafted VDOs from a connected port partner. A remote attacker can send a crafted Discover Modes ACK to overwrite adjacent memory.

Exploitation is possible after the port partner is set because incoming Discover Modes ACK messages are consumed without being correlated to a request sent by the port.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/3389c149c68c3fea61910ad5d34f7bf3bff44e32
• https://git.kernel.org/stable/c/4505f33dab56c274e82f47f94bf60a8cbf8f4b42
• https://git.kernel.org/stable/c/845598b154b9a92e9d279fafafa9405c121ae805
• https://git.kernel.org/stable/c/cbad85b446c06adbc5e5bed565871bb918ce9d32