CVE-2009-4147

CVE-2009-4147 describes a local privilege escalation vulnerability in the Run-Time Link-Editor (rtld) of FreeBSD versions 7.1 and 8.0. The vulnerability allows local users to gain elevated privileges by executing a setuid or setguid program, as rtld fails to clear sensitive environment variables like LD_LIBRARY_PATH. This allows an attacker to inject a malicious library via an untrusted search path. With a CVSS score of 7.2, this is a high-severity vulnerability with low attack complexity, enabling complete compromise of confidentiality, integrity, and availability. Exploit code is publicly available, including a Metasploit module and an ExploitDB entry, indicating its exploitability, though there is no evidence of active exploitation or significant community discussion.