CVE entry · CVE-2015-3246
CVE-2015-3246: Red Hat Libuser Race Condition Vulnerability
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.
- Actively exploited: added to CISA’s KEV catalog on August 26, 2026.
- Use by ransomware: not established so far.
- Remediation deadline for US federal agencies: September 9, 2026.
Description from CISA’s KEV catalog.
What to do
- Check whether your estate includes Red Hat Libuser, including internet-facing devices.
- Apply the vendor’s patch or mitigations (references below). Failing that, isolate the product or stop using it, as CISA requires of US federal agencies.
- An exploited vulnerability has often been used before it was fixed: look for signs of compromise, especially on internet-facing devices.