Description
Utempter allows device names that contain .. (dot dot) directory traversal sequences, which allows local users to overwrite arbitrary files via a symlink attack on device names in combination with an application that trusts the utmp or wtmp files.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 3 | utempter | 0.5.5-1.3EL.0 | RHSA-2004:174 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- UTempter 0.5.x - Multiple Local Vulnerabilities EDB-24027 · local · Apr 19, 2004 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 1
- RHSA-2004:174 Red Hat Security Advisory: utempter security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
References
- MDKSA-2004:031 vendor-advisory
- 1000752 vendor-advisory
- utemper-symlink(15904) vdb-entry
- RHSA-2004:174 vendor-advisory
- SSA:2004-110 vendor-advisory
- GLSA-200405-05 vendor-advisory
- oval:org.mitre.oval:def:10115 vdb-entry signature
- 10178 vdb-entry
- oval:org.mitre.oval:def:979 vdb-entry signature
- RHSA-2004:175 vendor-advisory