CVE-2026-5398

EUVD-2026-24589
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
8.4 HIGH
LOCAL
LOW
NONE
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
https://security.freebsd.org/advisories/FreeBSD-SA-26:10.tty.asc