GNUMP3d: Directory traversal and insecure temporary file creation

Background

GNUMP3d is a streaming server for MP3s, OGG vorbis files, movies and other media formats.

Description

Ludwig Nussel from SUSE Linux has identified two vulnerabilities in GNUMP3d. GNUMP3d fails to properly check for the existence of /tmp/index.lok before writing to the file, allowing for local unauthorized access to files owned by the user running GNUMP3d. GNUMP3d also fails to properly validate the “theme” GET variable from CGI input, allowing for unauthorized file inclusion.

Impact

An attacker could overwrite files owned by the user running GNUMP3d by symlinking /tmp/index.lok to the file targeted for overwrite. An attacker could also include arbitrary files by traversing up the directory tree (at most two times, i.e. “…/…”) with the “theme” GET variable.

Workaround

There is no known workaround at this time.

Resolution

All GNUMP3d users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=media-sound/gnump3d-2.9_pre7"