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HydraIRC - DCC Denial Of Service
Portcullis 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.
The vendor has been informed and the vulnerability has been fixed.
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
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.
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