CVE-2026-58093 — Kernel use-after-free via tty ioctls

Description (CNA)

The TIOCSCTTY ioctl handler drops the tty lock in order to acquire the process tree lock. After reacquiring the tty lock, the handler did not revalidate the state of the terminal, and could proceed to link a terminal that was concurrently being destroyed to the calling process' session. An unprivileged local user can exploit this race condition to escalate privileges.

Affected (CNA)

Vendor / product	Versions
FreeBSD / FreeBSD	affected 15.1-RELEASE before p3; affected 15.0-RELEASE before p13; affected 14.4-RELEASE before p9

CWE

CWE-362, CWE-416

References

https://security.freebsd.org/advisories/FreeBSD-SA-26:62.tty.asc

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.