Description
SCM_RIGHTS file descriptor passing did not preserve FD_RESOLVE_BENEATH when a descriptor was transferred. A process could clear the restriction by sending the descriptor to itself over a Unix domain socket. 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.
Affected products
freebsd: freebsd
References1
- security.freebsd.org/advisories/FreeBSD-SA-26:66.jail.asc PatchVendor Advisory
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 19 · as of 10 November 2026
- CWE
- CWE-273CWE-281
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