CVE-2026-101304 — Multiple jail filesystem root escapes
When fdescfs(4) was mounted in a jail with the "nodup" option, opening /dev/fd/N returned a descriptor that did not inherit FD_RESOLVE_BENEATH or the Capsicum capability rights …
Published: 2026-10-15 · CVSS: 7.1 · CVSS 3.1
When fdescfs(4) was mounted in a jail with the "nodup" option, opening /dev/fd/N returned a descriptor that did not inherit FD_RESOLVE_BENEATH or the Capsicum capability rights of descriptor N. 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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7