lighttpd: Script source disclosure

Background

lighttpd is a small-footprint, fast, compliant and very flexible web-server which is optimized for high-performance environments.

Description

lighttpd uses file extensions to determine which elements are programs that should be executed and which are static pages that should be sent as-is. By appending %00 to the filename, you can evade the extension detection mechanism while still accessing the file.

Impact

A remote attacker could send specific queries and access the source of scripts that should have been executed as CGI or FastCGI applications.

Workaround

There is no known workaround at this time.

Resolution

All lighttpd users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=www-servers/lighttpd-1.3.10-r1"