Never knew Downloader.Agent2.BBLD was so simple

Posted on Sun 29 April 2012 in blog

I had just started writing a new C++ console app (under Visual Studio 2010 10.0.40219.1 SP1Rel) to test something out, and had just this:

#include <stdio.h>
#include <Windows.h>

int main(int argc, char** argv)
{
    return 0;
}

I unintentionally clicked Start Debugging, and much to my surprise, the build had failed:

Build errors Link error

Really? How did I screw up something so simple? Several seconds later AVG popped up this "Resident Shield Alert":

AVG Resident Shield Alert

Are you kidding me? So I added a printf...

int main(int argc, char** argv)
{
    printf("WTF is going on\n");
    return 0;
}

Again, threat detected! This time, Downloader.Agent2.BAZE. I disabled AVG, built it again (successfully!) and threw the EXE into IDA, worried that I had some impressive virus injecting a trojan into EXEs I build. Nothing out of the ordinary found, just the typical complicated CRT startup code, and my simple main().

I uploaded it to VirusTotal to see if this was just AVG being retarded or what. It had a detection ratio of 8 / 42. Check out that link to see each AV and what they detected it as. It is important to note that AVG picked up the file before it had even finished building (hence the link error) with Resident Shield, but also the finished EXE with a manual scan.

"This is absurd!" I'm thinking. One more try....

int main(int argc, char** argv)
{
    printf("WTF is going on\n");
    getchar();
    printf("This is ridiculous\n");
    return 0;
}

Finally, this one built okay and AVG let it alone. Curious, I uploaded this one to VirusTotal too. It was picked up by only 1 / 42 AVs: McAfee-GW-Edition identified it as Heuristic.BehavesLike.Win32.Suspicious.H.

Sounds more like Heuristic.WeHaveNoIdea.FlagEverything.H