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.

CVSS v3 6.3 MEDIUM

6.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 5.2

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=24a227d0ab8576612194f8a56c2314389adc74a5
https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=3589787cd589b34bdd9265936e17190b6d3f17d1
https://www.vulncheck.com/advisories/acl-toctou-symlink-traversal-via-getfacl-setfacl-chacl

Configurations

No configuration.

History

29 Jun 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-29 14:16

Updated : 2026-06-29 19:22

NVD link : CVE-2026-54370

Mitre link : CVE-2026-54370

CVE.ORG link : CVE-2026-54370

JSON object : View

Products Affected

No product.

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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