Improper access control in FreeBSD - CVE-2026-101305
Published: September 30, 2026
Vulnerability details
The vulnerability allows a local user to escape the jail's filesystem root restriction.
The vulnerability exists due to improper access control in renameat(2) when renaming a directory relative to a restricted descriptor. A local user can rename a directory and use fchdir(2) to escape the jail's filesystem root restriction.
Exploitation requires a directory file descriptor received from another jail, and the directory must reside on a filesystem reachable from the jail's root.