CVE-2025-15547

Summary

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.

Affected Software

VendorProductVersion RangeStatus
FreeBSDFreeBSD14.3-RELEASE < p8affected
FreeBSDFreeBSD13.5-RELEASE < p9affected

Weaknesses

  • CWE-269: CWE-269 Improper Privilege Management

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References