CVE-2026-49421unlinkat(2) ignores AT_RESOLVE_BENEATH flag
Updated under an hour ago ()
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It affects FreeBSD. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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Free account, 1 product
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.
- CVSS
- 7.1 HIGH (v3.1, CISA ADP)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
- Weakness (CWE)
- CWE-273
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- freebsd
- NVD analysis
- Analyzed
- Record last updated
- Aug 26, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
FreeBSD FreeBSD freebsd:freebsd (from the name) | from 15.1-RELEASE before p1; from 15.0-RELEASE before p11; from 14.4-RELEASE before p7; from 14.3-RELEASE before p16 | CNA record |
freebsd freebsd freebsd:freebsd | 14.3; 14.3; 14.3; 14.3; 14.3; 14.3; 14.3; 14.3; and 30 more ranges | NVD |
References
- https://security.freebsd.org/advisories/FreeBSD-SA-26:42.unlinkat.ascvendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.