CVE-2009-4146

Severity: high (CVSS 7.2 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2009-12-02 · updated 2026-06-16
Weakness: CWE-264

Description

The _rtld function in the Run-Time Link-Editor (rtld) in libexec/rtld-elf/rtld.c in FreeBSD 7.1, 7.2, and 8.0 does not clear the LD_PRELOAD environment variable, which allows local users to gain privileges by executing a setuid or setguid program with a modified LD_PRELOAD variable containing an untrusted search path that points to a Trojan horse library, a different vector than CVE-2009-4147.

Affected products

FreeBSD: 7.1, 7.2, 8.0

References

http://packetstormsecurity.com/files/152997/FreeBSD-rtld-execl-Privilege-Escalation.html
http://people.freebsd.org/~cperciva/rtld.patch
http://secunia.com/advisories/37517
http://www.securityfocus.com/archive/1/508142/100/0/threaded
http://www.securityfocus.com/archive/1/508146/100/0/threaded
http://www.securityfocus.com/archive/1/508168/100/0/threaded
http://www.securityfocus.com/bid/37154
http://www.securitytracker.com/id?1023250
http://packetstormsecurity.com/files/152997/FreeBSD-rtld-execl-Privilege-Escalation.html
http://people.freebsd.org/~cperciva/rtld.patch
http://secunia.com/advisories/37517
http://www.securityfocus.com/archive/1/508142/100/0/threaded

Get alerted when CVE-2009-4146 or the next vulnerability affects your stack