CVE-2026-58093: Freebsd

High severity, CVSS 7.0. EPSS: 0.1% chance of exploitation in the next 30 days.

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 products

• Freebsd Freebsd: version 14.4 only; version 15.0 only; version 15.1 only

Published 2026-08-26. Last modified 2026-09-24.