CVE-2026-54370

high

Description

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.

References

https://www.vulncheck.com/advisories/acl-toctou-symlink-traversal-via-getfacl-setfacl-chacl

https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=3589787cd589b34bdd9265936e17190b6d3f17d1

https://cgit.git.savannah.nongnu.org/cgit/acl.git/commit/?id=24a227d0ab8576612194f8a56c2314389adc74a5

Details

Source: Mitre, NVD

Published: 2026-06-29

Updated: 2026-06-29

Risk Information

CVSS v2

Base Score: 5.5

Vector: CVSS2#AV:L/AC:H/Au:S/C:C/I:C/A:N

Severity: Medium

CVSS v3

Base Score: 6.3

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

Severity: Medium

CVSS v4

Base Score: 7.2

Vector: 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

Severity: High