Red Hat Libuser
CVE-2015-3246: Red Hat Libuser Race Condition Vulnerability
What it is
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.
What to do
Schedule the vendor fix into this week’s change window, prioritising internet-facing and business-critical systems. Confirm the fix is applied everywhere, not just where it was easy.
- Priority
- This week: Schedule into this week’s change window.
- Severity (CVSS)
- 7.4 high
- CISA assessment (SSVC)
- actively exploited; needs manual effort per target; total control of the affected system
- Exploit probability (EPSS, 30 days)
- 8.4%, higher than 94% of all CVEs
- Added to CISA KEV
- 26 August 2026
- CISA fix-by date
- 9 September 2026 (US federal agencies; a sensible deadline for everyone)
- Ransomware use
- Not known
- Weakness
- CWE-264, CWE-367
References
- NIST NVD entry
- CISA KEV entry
- lists.fedoraproject.org/pipermail/package-announce/2015-August/163044.html
- lists.fedoraproject.org/pipermail/package-announce/2015-July/162947.html
- lists.opensuse.org/opensuse-security-announce/2015-08/msg00000.html
- rhn.redhat.com/errata/RHSA-2015-1482.html
- rhn.redhat.com/errata/RHSA-2015-1483.html
- www.securityfocus.com/bid/76022
Sources: CISA Known Exploited Vulnerabilities · FIRST Exploit Prediction Scoring System (EPSS) · NIST National Vulnerability Database · CISA Vulnrichment (SSVC), via the CVE Program. This product uses data from the NVD API but is not endorsed or certified by the NVD. Summaries are machine-written from CISA’s description; treat the vendor’s advisory as the authority for fixes.