SB2026102448 - Always-Incorrect Control Flow Implementation in Linux kernel serial 8250 driver

Description

This security bulletin contains information about 1 vulnerability.

1) Always-Incorrect Control Flow Implementation (CVE-ID: CVE-2026-98883)

CWE-ID: CWE-670 - Always-Incorrect Control Flow Implementation

CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local privileged user to trigger an erroneous kernel warning during initialization of an affected serial port.

The vulnerability exists due to improper handling of the UPIO_AU UART I/O type in set_io_from_upio() when probing affected 8250 serial ports on MIPS Alchemy systems. A local privileged user can trigger serial-port initialization, if able to initiate probing, to generate an erroneous unsupported-UART warning despite the port parameters already being configured.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/49fa670efdfdd27e29145cbd2beef065c08717ef
• https://git.kernel.org/stable/c/9f67997353caa29c6a080789a1fb6e01fb50c118