Description
The kernel function that implements unlinkat(2) and funlinkat(2) validated the AT_RESOLVE_BENEATH flag but failed to pass it through to the underlying path lookup. The flag was silently dropped, so path resolution was not actually restricted. A process that uses AT_RESOLVE_BENEATH with unlinkat(2) or funlinkat(2) to confine path resolution can in fact resolve paths above the starting directory. A caller relying on this flag for path containment may delete files outside the intended directory tree.
Affected products
freebsd: freebsd
References1
- security.freebsd.org/advisories/FreeBSD-SA-26:42.unlinkat.asc Vendor Advisory
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H - EPSS — exploit probability
- 0% percentile: 3 · as of 10 November 2026
- CWE
- CWE-273
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