CVE-2026-54370 (GCVE-0-2026-54370)

Vulnerability from cvelistv5 – Published: 2026-06-29 12:38 – Updated: 2026-07-14 21:33 X_Open Source
VLAI
Title
acl < 2.4.0 TOCTOU Symlink Traversal via getfacl/setfacl/chacl
Summary
acl before version 2.4.0 contains a time-of-check to time-of-use (TOCTOU) race condition vulnerability that allows local attackers to escalate privileges by replacing a pathname component with a symbolic link between an lstat() check and subsequent symlink-following operations such as stat(), chown(), chmod(), acl_get_file(), and acl_set_file(). Attackers who control a pathname component can redirect file access control list operations to arbitrary files when getfacl, setfacl, or chacl is invoked by a privileged process over an attacker-controlled path, resulting in local privilege escalation.
Severity
7.2 (High)
CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
6.3 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-29 14:49 UTC
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7165 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
acl project acl Affected: 0 , < 2.4.0 (semver)
    cpe:2.3:a:acl_project:acl:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-06-29 00:00
Credits
Andrew Tridgell Andreas Gruenbacher
Show details on NVD website
To clipboard 

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