Distributed under a GNU General Public license, KTorrent is a torrent client written in C++ for KDE. Feature wise, the client can compete with other popular clients, supporting protocol encryption, UDP trackers and web-seeding to name a few.
One feature, however, is posing a security threat to the user. According to a security alert, multiple serious vulnerabilities have been found in the client.
With a severity rated as ‘High’, the vulnerabilities are to be found in the client’s web interface plugin. Since the plugin does not successfully restrict access to the clients torrent upload functionality and fails to sanitize request parameters, it is vulnerable to exploitation.
The flaws can allow a malicious remote attacker to send specially crafted parameters to the web interface. This could enable remote arbitrary torrent uploads along with the possibility of remote code execution, within the same privileges as the KTorrent process itself.
A temporary workaround solution is to disable the web interface plugin. This can be achieved by clicking “plugins” in the config menu and unchecking the “Web Interface” checkbox.
Versions affected by this issue are 2.2.8 and earlier, so users updating to the latest version are protected from these security vulnerabilities.