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.
Fix
Patch, vendor advisory and mitigation references on NVD 1
- https://security.freebsd.org/advisories/FreeBSD-SA-26:66.jail.asc Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 6
- StatusAnalyzed → ModifiedNVD modified 2026-10-20 17:17
- Cpes+29 CPE criteria (now 29)NVD modified 2026-10-20 00:18
- StatusAwaiting Analysis → AnalyzedNVD modified 2026-10-20 00:18
- CVSS7.1 (v3.1, CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N)NVD modified 2026-10-20 00:18
- StatusReceived → Awaiting AnalysisNVD modified 2026-10-15 16:17
- First seenunscoredNVD modified 2026-10-15 07:17
Affected (CPE criteria) 29
cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p2:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p3:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p4:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p5:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p6:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p7:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p8:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.4:p9:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:14.5:-:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p10:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p11:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p12:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p13:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p6:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p7:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p8:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.0:p9:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.1:-:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.1:p1:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.1:p2:*:*:*:*:*:*cpe:2.3:o:freebsd:freebsd:15.1:p3:*:*:*:*:*:*
References 1
- https://security.freebsd.org/advisories/FreeBSD-SA-26:66.jail.asc Patch, Vendor Advisory