CVE-2026-5398

HIGH

Kernel use-after-free bug in the TIOCNOTTY handler

Title source: cna

Description

The implementation of TIOCNOTTY failed to clear a back-pointer from the structure representing the controlling terminal to the calling process' session. If the invoking process then exits, the terminal structure may end up containing a pointer to freed memory. A malicious process can abuse the dangling pointer to grant itself root privileges.

References (1)

[Vendor Advisory] https://security.freebsd.org/advisories/FreeBSD-SA-26:10.tty.asc

Scores

CVSS v3 8.4

EPSS 0.0001

EPSS Percentile 2.2%

Attack Vector LOCAL

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Details

CWE

CWE-416

Status published

Products (4)

FreeBSD/FreeBSD 13.5-RELEASE - p12

FreeBSD/FreeBSD 14.3-RELEASE - p11

FreeBSD/FreeBSD 14.4-RELEASE - p2

FreeBSD/FreeBSD 15.0-RELEASE - p6

Published Apr 22, 2026

Tracked Since Apr 22, 2026