CVE-2019-19726
OpenBSD 6.x - Dynamic Loader Privilege Escalation
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
8Exploited in Wild
-Decision
Descriptions
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.
OpenBSD versiones hasta 6.6, permite a usuarios locales escalar a root porque una comprobación de LD_LIBRARY_PATH en los programas setuid puede ser vencida estableciendo un límite de recursos de RLIMIT_DATA muy pequeño. Al ejecutar chpass o passwd (que son root de setuid), en la función _dl_setup_env en el archivo ld.so intenta eliminar LD_LIBRARY_PATH del entorno, pero presenta un fallo cuando no puede asignar memoria. Por lo tanto, el atacante es capaz de ejecutar su propio código de biblioteca como root.
Dubbed Looney Tunables, Qualys discovered a buffer overflow vulnerability in the glibc dynamic loader's processing of the GLIBC_TUNABLES environment variable. This vulnerability was introduced in April 2021 (glibc 2.34) by commit 2ed18c.
CVSS Scores
SSVC
- Decision:-
Timeline
- 2019-12-11 CVE Reserved
- 2019-12-12 CVE Published
- 2019-12-12 First Exploit
- 2024-08-05 CVE Updated
- 2025-03-30 EPSS Updated
- ---------- Exploited in Wild
- ---------- KEV Due Date
CWE
- CWE-269: Improper Privilege Management
CAPEC
References (18)
| URL | Date | SRC |
|---|---|---|
| https://packetstorm.news/files/id/174986 | 2023-10-06 | |
| https://packetstorm.news/files/id/155658 | 2019-12-12 | |
| https://packetstorm.news/files/id/155764 | 2019-12-27 | |
| https://www.exploit-db.com/exploits/47780 | 2019-12-16 | |
| https://www.exploit-db.com/exploits/47803 | 2019-12-30 | |
| http://packetstormsecurity.com/files/155658/Qualys-Security-Advisory-OpenBSD-Dynamic-Loader-Privilege-Escalation.html | 2024-08-05 | |
| http://seclists.org/fulldisclosure/2019/Dec/31 | 2024-08-05 | |
| https://seclists.org/bugtraq/2019/Dec/25 | 2024-08-05 |
| URL | Date | SRC |
|---|---|---|
| https://www.openbsd.org/errata66.html | 2023-10-06 |
| URL | Date | SRC |
|---|