Kernel use-after-free bug in the TIOCNOTTY handler_CVE-2026-5398

8.4 / 10

HIGH

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

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.

Basic Information

ID CVE-2026-5398

Source freebsd

Published Apr 22, 2026 at 02:23

Modified Apr 22, 2026 at 14:24

Affected Product

Vendor FreeBSD

Product FreeBSD

Version 15.0-RELEASE

Affected Versions FreeBSD FreeBSD 15.0-RELEASE
FreeBSD FreeBSD 14.4-RELEASE
FreeBSD FreeBSD 14.3-RELEASE
FreeBSD FreeBSD 13.5-RELEASE

CWE Classification

CWE-416

References

security.freebsd.org /advisories/FreeBSD-SA-26:10.tty.asc

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    "published": "2026-04-22T02:23:56.767Z",
    "modified": "2026-04-22T14:24:21.661Z",
    "type": "cve",
    "title": "Kernel use-after-free bug in the TIOCNOTTY handler",
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