Red Hat Libuser Race Condition Vulnerability (CVE-2015-3246)
Severity: high · Patch status: unknown · Since 2026-08-26 · CVE-2015-3246
Red Hat libuser contains a race condition vulnerability that allows authenticated local users to corrupt the /etc/passwd file to cause a denial of service or privilege escalation. CISA added CVE-2015-3246 to its Known Exploited Vulnerabilities catalog on Aug 26, 2026, which means attackers are exploiting it in the wild.
What to do
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- US federal agencies must remediate by Sep 9, 2026 (BOD 22-01); treat that as the outer limit.
Sources
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