CVE-2026-23472

A flaw was found in the Linux kernel's serial core component. An inconsistency between the uart_write_room() and uart_write() functions, specifically when handling PORT_UNKNOWN serial ports with a NULL transmit buffer, can lead to an infinite loop. This allows a local user or process to trigger a system hang, resulting in a Denial of Service (DoS).

The fix aligns uart_write_room() with uart_write() when no transmit buffer exists. Exploitation requires a path that opens such a port and exercises the buggy loop; impact is a local or subsystem hang, not remote code execution by itself.

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.