CVE-2026-49421
Last modified
CVE-2026-49421 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. 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. EPSS estimates a 0.09% chance of exploitation in the next 30 days.
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.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Freebsd | Freebsd | 14.3 |
| Freebsd | Freebsd | 14.4 |
| Freebsd | Freebsd | 15.0 |
| Freebsd | Freebsd | 15.1 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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