Bug 2452956 (CVE-2026-25704)

Summary: CVE-2026-25704 cosmic-greeter: cosmic-greeter: Privilege escalation via TOCTOU race condition
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in cosmic-greeter. This vulnerability is a Time-of-check Time-of-use (TOCTOU) race condition, which occurs when an application checks for a condition and then uses the result of that check, but the condition changes between the check and the use. A local attacker can exploit this flaw to regain privileges that should have been dropped.
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Bug Depends On: 2452966    
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Description OSIDB Bzimport 2026-03-30 09:01:42 UTC 
A Privilege Dropping / Lowering Errors/Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in  cosmic-greeter can allow an attacker to regain privileges that should have been dropped and abuse them in the racy checking logic.




This issue affects cosmic-greeter before https://github.Com/pop-os/cosmic-greeter/pull/426.