VDB-374620 · CVE-2026-54370 · GCVE-0-2026-54370

acl up to 2.3.x Pathname lstat toctou

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.3	$0-$5k	1.22-

Summaryinfo

A vulnerability categorized as problematic has been discovered in acl up to 2.3.x. This issue affects the function lstat of the component Pathname. Executing a manipulation can lead to toctou. This vulnerability is registered as CVE-2026-54370. The attack needs to be launched locally. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in acl up to 2.3.x and classified as problematic. This vulnerability affects the function lstat of the component Pathname. The manipulation with an unknown input leads to a toctou vulnerability. The CWE definition for the vulnerability is CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The weakness was published by Andrew Tridgell and Andreas Gruenbacher. The advisory is shared for download at cgit.git.savannah.nongnu.org. This vulnerability was named CVE-2026-54370 since 06/12/2026. The exploitation appears to be difficult. The attack needs to be approached locally. There are known technical details, but no exploit is available.

Upgrading to version 2.4.0 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at cgit.git.savannah.nongnu.org. The best possible mitigation is suggested to be upgrading to the latest version.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.5
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Toctou
CWE: CWE-367 / CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: acl 2.4.0
Patch: cgit.git.savannah.nongnu.org

Timelineinfo

06/12/2026 CVE reserved
06/29/2026 +17 days Advisory disclosed
06/29/2026 +0 days VulDB entry created
06/29/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: cgit.git.savannah.nongnu.org
Researcher: Andrew Tridgell, Andreas Gruenbacher
Status: Confirmed

CVE: CVE-2026-54370 (🔒)
GCVE (CVE): GCVE-0-2026-54370
GCVE (VulDB): GCVE-100-374620

Entryinfo

Created: 06/29/2026 16:37
Changes: 06/29/2026 16:37 (77)
Complete: 🔍
Cache ID: 216::103