cve/2019/CVE-2019-19726.md

### [CVE-2019-19726](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-19726)
![](https://img.shields.io/static/v1?label=Product&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=n%2Fa&color=blue)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=brighgreen)

### Description

OpenBSD through 6.6 allows local users to escalate to root because a check for LD_LIBRARY_PATH in setuid programs can be defeated by setting a very small RLIMIT_DATA resource limit. When executing chpass or passwd (which are setuid root), _dl_setup_env in ld.so tries to strip LD_LIBRARY_PATH from the environment, but fails when it cannot allocate memory. Thus, the attacker is able to execute their own library code as root.

### POC

#### Reference
- http://packetstormsecurity.com/files/155658/Qualys-Security-Advisory-OpenBSD-Dynamic-Loader-Privilege-Escalation.html
- http://packetstormsecurity.com/files/155764/OpenBSD-Dynamic-Loader-chpass-Privilege-Escalation.html
- http://packetstormsecurity.com/files/174986/glibc-ld.so-Local-Privilege-Escalation.html
- http://seclists.org/fulldisclosure/2019/Dec/31
- http://seclists.org/fulldisclosure/2023/Oct/11
- http://www.openwall.com/lists/oss-security/2023/10/03/2
- https://seclists.org/bugtraq/2019/Dec/25
- https://www.openwall.com/lists/oss-security/2019/12/11/9

#### Github
- https://github.com/ARPSyndicate/cvemon
- https://github.com/alphaSeclab/sec-daily-2019
- https://github.com/anoaghost/Localroot_Compile
- https://github.com/bcoles/local-exploits
- https://github.com/vshaliii/DC-1-Vulnhub-Walkthrough