CVE-2026-49421 (GCVE-0-2026-49421)

Vulnerability from cvelistv5 – Published: 2026-08-19 05:25 – Updated: 2026-08-26 17:44
VLAI
Title
unlinkat(2) ignores AT_RESOLVE_BENEATH flag
Summary
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.
Severity
7.1 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-26 17:44 UTC
CWE
  • CWE-273 - Improper Check for Dropped Privileges
Assigner
References
Impacted products
Vendor Product Version
FreeBSD FreeBSD Affected: 15.1-RELEASE , < p1 (release)
Affected: 15.0-RELEASE , < p11 (release)
Affected: 14.4-RELEASE , < p7 (release)
Affected: 14.3-RELEASE , < p16 (release)
Create a notification for this product.
Date Public
2026-06-30 20:00
Credits
Yuxiang Yang, Yizhou Zhao, Ao Wang, Xuewei Feng, Qi Li, and Ke Xu from Tsinghua University using GLM-5.1 from Z.ai
Show details on NVD website
To clipboard 

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