A vulnerability in the Snort open-source intrusion protection software could open up networks to remote attackers.
A buffer overflow flaw exists in a Snort sensor designed to detect the Back Orifice remote-controlled Trojan horse, Snort developer Sourcefire has said in an advisory.
Sourcefire said an attacker could take over a system running Snort 2.4.0 or higher by sending a specially crafted network packet.
The Snort software is designed to protect networks from attack and is installed on more than 100,000 systems, according to Sourcefire. The software is also bundled with third-party security packages.
Internet Security Systems discovered the Snort flaw. Sourcefire has released Snort version 2.4.3 to fix the problem.
Sourcefire is being acquired by Check Point, which has said it will keep Snort as an open-source product.