CVE-2025-15547
Jail escape by a privileged user via nullfs
- State
- Published
- Severity
- 8.8 High
- Published
- Mar 9, 2026
- Updated
- Mar 10, 2026
- Reserved
- Jan 26, 2026
Description
By default, jailed processes cannot mount filesystems, including nullfs(4). However, the allow.mount.nullfs option enables mounting nullfs filesystems, subject to privilege checks.
If a privileged user within a jail is able to nullfs-mount directories, a limitation of the kernel's path lookup logic allows that user to escape the jail's chroot, yielding access to the full filesystem of the host or parent jail.
In a jail configured to allow nullfs(4) mounts from within the jail, the jailed root user can escape the jail's filesystem root.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 8.8 High | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H | CISA-ADP |
Weaknesses
- CWE-269 Improper Privilege Management
Affected Products
| Product | Versions |
|---|---|
FreeBSDFreeBSD |
|
References
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.