ctcphandler.cpp in Quassel before 0.6.3 and 0.7.x before 0.7.1 allows remote attackers to cause a denial of service (unresponsive IRC) via multiple Client-To-Client Protocol (CTCP) requests in a PRIVMSG message.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.012
EPSS Ranking 77.9%