Linux Security Flaw Detailed

Internet Security Systems is warning Linux users of a back-door security flaw that carries ISS's highest danger rating.

The company's vulnerability-assessment team, or "X-Force," as it is known, said a back-door vulnerability exists for any user running a full version of Red Hat Linux Piranha, which contains Linux Virtual Server software, a Web-based GUI, as well as monitoring and failover applications. ISS and Red Hat are providing a fix for the problem.

According to ISS, an undocumented back-door password exists in the GUI portion of Piranha that may allow remote users to execute commands on the server from a remote location and may provide access to other systems. This security flaw has been given a "5" rating, on a scale from 1 to 5, because of the flaw's inherent ability to provide damaging access to attackers. The flaw is present in version 0.4.12 of the Piranha GUI, which is part of the latest Red Hat Linux 6.2 distribution. Early versions of Red Hat are not vulnerable.

A security breach is possible even if Linux Virtual Server is not used on the system. The system is vulnerable if the affected Piranha GUI package is installed and the administrator has not changed the password. Chris Rouland, director of X-Force at ISS, Atlanta, said he does not believe the back door was installed with malicious intent, but the vulnerability does reinvigorate the debate between open source and closed source software.

"I think it was just an engineering mistake," Rouland said. "[Open source software doesn't have] an engineering organization whose role or job it is to provide quality assurance to commercial software. The upside of open source is that everyone can see it, so if there are glaring holes, you have peer revue."

Red Hat has provided updated Piranha, Piranha-doc, and Piranha GUI packages 0.4.13 to 1, and recommends administrators be sure a new password is installed following the installation.