Vulnerability in FreeBSD

[ Description ]Official description

renameat(2) did not enforce FD_RESOLVE_BENEATH on its directory arguments. A jailed process could rename a directory relative to a restricted descriptor, then escape the jail root via fchdir(2). This requires the directory to reside on a filesystem that is also reachable from the jail's root. A process in a jail that has received a directory file descriptor from another jail can use these techniques to escape the jail's filesystem root restriction.

[ Fixes ]Fixes and patches

• Patch on security.freebsd.orgVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD

[ Advisories ]Government CERT advisories

• BSI CERT-Bund29 Sep 2026WID-SEC-2026-3664

  FreeBSD Project FreeBSD OS: Multiple vulnerabilities Translated from German

  CVE-2026-84783CVE-2026-101305CVE-2026-101306+7 more CVEs

[ References ]References

• security.freebsd.org/advisories/FreeBSD-SA-26:66.jail.ascPatchVendor Advisory