Type Trojan
Description
Troj/Mirseed-A is an IRC Trojan that spams IRC channels with the message "[Info] Speed up your mIRC DCC Transfer by up to 75% with DCC Speed-Up Tool, get it now at ww.freewebs.com/mircupdate/mircspeedup.exe -Regards, Network Staff".
The EXE referenced in the URL is Troj/Mirseed-A.
Troj/Mirseed-A copies itself to C:\sysexec.exe and sets the following registry entry:
HKLM\Software\Microsoft\Windows\CurrentVersion\Run\
System Root Configuration = C:\sysexec.exe
The Trojan also drops an IRC script into C:\memory.sys that it uses for spamming and logs onto certain predefined IRC channels.
http://www.sophos.com/virusinfo/analyses/trojmirseeda.html

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