[R2] Nessus 4.2.0 Fixes Third-party Library Vulnerability

Early 4.0.x versions of Nessus for bundle the Qt browser. Nessus versions for Windows, not Unix, were affected by the following issue.

QtWeb Browser is prone to a flaw in the way it loads dynamic-link libraries (e.g. wintab32.dll). The program uses a fixed path to look for specific files or libraries. This path includes directories that may not be trusted or under user control. By placing a custom version of the file or library in the path, the program will load it before the legitimate version. This allows an attacker to inject custom code that will be run with the privilege of the program or user executing the program. This can be done by tricking a user into opening a HTML file from the local file system or a USB drive in some cases. This attack can be leveraged remotely in some cases by placing the malicious file or library on a network share or extracted archive downloaded from a remote source.

Note that this issue was originally reported to Tenable, and publicly, as a vulnerability in Nessus. Subsequent examination by Tenable determined it related to QtWeb. Many additional software packages from other vendors were reported vulnerable in the weeks after the QtWeb disclosure. Tenable had already upgraded to a fixed version of QtWeb before this was disclosed.