Privilege escalation in Freebsd

CVE-2025-15547

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.

Vulnerability class: Privilege Escalation

EPSS: 0.001 (1.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

Affected products

  • Freebsd — versions 14.3, 13.5, 14.3-RELEASE

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-15547?
CVE-2025-15547 is a high-severity vulnerability in Freebsd, classified under Improper Privilege Management. CVSS score: 8.8/10. Published 2026-03-09.
How severe is CVE-2025-15547?
High severity. CVSS v3 base score is 8.8 out of 10.