CVE-2015-3246mediumunder attackCWE-367

CVE-2015-3246

78Vexday Risk Score

Patch now. It under exploitation confirmed by CISA and has a working public exploit.

ssvc Actcvss 5.1epss 8.8%

from disclosure to weapon0 days

Published on NVDAug 11

1st PoCJul 27

metasploitJul 24

CISA KEV+4033d

exploitation probability

8.8%top 5% of all CVEs

observed exploitation

yesCISA + VulnCheck

4 public exploit(s)

Action required by CISAfederal deadline: 2026-09-09

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.

In short

libuser before version 0.56.13-8 and 0.60 before 0.60-7 directly modifies the /etc/passwd file without proper safeguards, allowing local users to cause the system to enter an inconsistent state by triggering an error during file modification. This can disrupt user authentication and system functionality.

Technical detail

A race condition or improper error handling in libuser's direct modification of /etc/passwd (CWE-367: Time-of-check Time-of-use) enables local attackers to induce inconsistent file state. When combined with CVE-2015-3245, this can facilitate privilege escalation due to unsafe file manipulation during critical system operations.

Summary generated and translated by AI from the official description.

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.

CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

n/a · n/a

public PoCs found — 4✓ VexDay Proof

exploitdb✓ VexDay Proofwww.exploit-db.com/exploits/37706 exploitdb✓ VexDay Proofwww.exploit-db.com/exploits/44633 githubgithub.com/HORKimhab/CVE-2015-3246★ 0 cve_referencewww.exploit-db.com/exploits/44633/unverified

⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.

References

http://lists.fedoraproject.org/pipermail/package-announce/2015-August/163044.html http://lists.fedoraproject.org/pipermail/package-announce/2015-July/162947.html http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00000.html http://rhn.redhat.com/errata/RHSA-2015-1482.html http://rhn.redhat.com/errata/RHSA-2015-1483.html https://access.redhat.com/articles/1537873 https://blog.talosintelligence.com/uat-10147-chinese-speaking-adversary-integrates-agentic-ai-into-post-compromise-operations/https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2015-3246 https://www.exploit-db.com/exploits/44633/https://www.qualys.com/2015/07/23/cve-2015-3245-cve-2015-3246/cve-2015-3245-cve-2015-3246.txt http://www.securityfocus.com/bid/76022 http://www.securitytracker.com/id/1033040