CyberSecBulletin
CVE-2026-54369NVD status: Deferred

acl: Improper Link Resolution Before File Access

CVE-2026-54369 is a high-severity improper link resolution before file access vulnerability in acl from Acl Project, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 2.4.0 as the first without the flaw, so updating acl to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.15% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update acl to 2.4.0 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
Acl Projectaclbefore 2.4.02.4.0
Red HatRed Hat Enterprise Linux 10Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 10.0 Extended Update SupportNot specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 9Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.22Not specified in the recordNot stated
Red HatRed Hat Discovery 2Not specified in the recordNot stated
Red HatRed Hat Hardened ImagesNot specified in the recordNot stated
Red HatRed Hat Insights proxy 1.5Not specified in the recordNot stated
Red HatRed Hat OpenShift distributed tracing 3.10.2Not specified in the recordNot stated
Red HatRed Hat Update Infrastructure 5Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 6Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 7Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.08.4HighCNA (vulncheck.com)
CVSS 3.17.1HighCNA (vulncheck.com)
CVSS 3.17.1HighCNA

Official description

acl before version 2.4.0 contains a symlink traversal vulnerability in the libacl pathname-based functions acl_get_file(), acl_set_file(), acl_extended_file(), and acl_delete_def_file() that allows local attackers to escalate privileges by replacing any pathname component with a symbolic link. Attackers who control any component of a pathname processed by a privileged caller can redirect ACL read or write operations to arbitrary files or directories, enabling unauthorized manipulation of access control lists and local privilege escalation.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Link Resolution Before File Access

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How developers prevent this class of flaw

  • Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

More Improper Link Resolution Before File Access vulnerabilities (CWE-59)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Link Resolution Before File Access vulnerabilities

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