Bug 2490279 (CVE-2026-54370)

Summary: CVE-2026-54370 acl: TOCTOU Symlink Traversal via getfacl/setfacl
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, security-response-team, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A time-of-check to time-of-use (TOCTOU) race condition vulnerability was found in `acl`. By replacing a pathname component with a symbolic link between a security check and subsequent file operations, an attacker can redirect file access control list operations. This occurs when privileged processes invoke `getfacl` or `setfacl` over an attacker-controlled path, potentially leading to local privilege escalation.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2494173    
Bug Blocks:    
Deadline: 2026-06-29   

Description OSIDB Bzimport 2026-06-18 10:59:14 UTC 
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 or setfacl is invoked by a privileged process over an attacker-controlled path, resulting in local privilege escalation.