CVE-2023-54299

A NULL pointer dereference flaw was found in the Linux kernel's USB Type-C subsystem. When certain USB hubs perform a data role swap after entering DisplayPort Alt Mode, all alternate modes are unregistered. If the hub continues sending Attention messages afterward, the typec_altmode_attention() function dereferences a NULL partner pointer, causing a kernel crash.

This requires specific USB hub hardware that performs data role swaps after entering alt mode. The issue is triggered by physical USB device behavior rather than software attack. Systems without USB-C with DisplayPort Alt Mode capability are unaffected.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.