Vulnerability in Acl Project
CVE-2026-54370
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.
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
EPSS: 0.001 (0.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Acl Project — versions 0
Weakness classification (CWE)
References
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (issue-tracking)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-54370?
- CVE-2026-54370 is a medium-severity vulnerability in Acl Project, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 6.3/10. Published 2026-06-29.
- How severe is CVE-2026-54370?
- Medium severity. CVSS v3 base score is 6.3 out of 10.