PT-2026-30166 · Linux · Linux Kernel

Published 2026-04-03 · Updated 2026-04-20 · CVE-2026-23472

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The Linux kernel contains a flaw in the serial core related to handling transmission for unknown ports (PORT UNKNOWN). Inconsistencies between uart write room() and uart write() when xmit buf is NULL can lead to an infinite loop in drivers that use tty write room() to determine write availability. Specifically, uart write room() may return a value greater than zero even when xmit buf is NULL, while uart write() returns zero in the same scenario. This discrepancy causes drivers like caif serial to enter an infinite loop in their handle tx() function when used with PORT UNKNOWN serial ports, resulting in system hangs.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Infinite Loop

Weakness Enumeration

CWE-835

Related Identifiers

CVE-2026-23472

Affected Products

Linux Kernel

References · 16

• https://security-tracker.debian.org/tracker/CVE-2026-23472 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2404-CVE-2026-23472 · Vendor Advisory
• https://osv.dev/vulnerability/BELL-CVE-2026-23472 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-23472 · Vendor Advisory
• https://git.kernel.org/stable/c/bc70f2b36cf474d5cc8ecbcaf57f3e326fdec67c · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-23472 · Security Note
• https://git.kernel.org/stable/c/efe85a557186b7fe915572ae93a8f3f78bfd9a22 · Patch
• https://osv.dev/vulnerability/ROOT-OS-UBUNTU-2204-CVE-2026-23472 · Vendor Advisory
• https://git.kernel.org/stable/c/455ce986fa356ff43a43c0d363ba95fa152f21d5 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-23472 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-23472 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-23472 · Security Note
• https://docs.bell-sw.com/security/cves/CVE-2026-23472 · Note
• https://git.kernel.org/linus/455ce986fa356ff43a43c0d363ba95fa152f21d5 · Note
• https://twitter.com/CVEnew/status/2040111853813236145 · Twitter Post