Security Advisory 07-008 – Denial of service due to format string vulnerability in DCC file transfer
Vulnerability discovery and development:
Portcullis Security Testing Services
Credit for Discovery:
Nico Leidecker of Portcullis Computer Security Ltd discovered this vulnerability. Further research was then carried out.
Version 0.3.151 was tested to be vulnerable.
HydraIRC is an IRC client supporting DCC file transfers. The client is prone to a format string vulnerability as it passes user input to a function expecting a format string. This only occurs, when the DCC file transfer negotiation fails.
By sending a special crafted DCC file transfer request to the victim, an attacker is then able to conduct a Denial of Service attack against them.
Proof of concept exploit code is available.
The vendor has been informed and the vulnerability has been fixed.
Permission is hereby granted for the electronic redistribution of this information. It is not to be edited or altered in any way without the express written consent of Portcullis Computer Security Limited.