Red Hat Libuser Race Condition Vulnerability
n/a — n/a
libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.
5.1
8.8%
Vector breakdown
- Attack vector
- Local
- Attack complexity
- High
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- Aug 11, 2015
- Modified
- Aug 27, 2026
- Added to KEV
- Aug 26, 2026
- Federal patch due
- Sep 9, 2026
CISA required action
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.
Weakness classification
Affected packages
Proof-of-concept & exploitation references
Weaponization
Public repositories whose name or description references CVE-2015-3246, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit - cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.
No public GitHub repositories referencing CVE-2015-3246 were found at last check. Absence here is not proof no exploit exists - see the references below for vendor advisories and write-ups.
References
Frequently asked questions
What is CVE-2015-3246?
libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.
How severe is CVE-2015-3246?
CVE-2015-3246 has a CVSS base score of 5.1 out of 10 (CVSS 3.1).
Is CVE-2015-3246 actively exploited in the wild?
Yes. CVE-2015-3246 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added Aug 26, 2026, meaning CISA has confirmed evidence of active exploitation.
What is the EPSS score for CVE-2015-3246?
8.8% - meaning FIRST.org's EPSS model estimates a 8.8% probability this vulnerability will be exploited in the wild within 30 days (95% percentile among all scored CVEs).
What type of vulnerability is CVE-2015-3246?
CVE-2015-3246 is classified under CWE-264, CWE-367.
Cross-checked against
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