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 #12327  by Buster_BSA
 Sun Mar 25, 2012 7:59 am
EP_X0FF wrote:
Maxstar wrote:in a virtual mode there not working.
I assume all three samples are identical, so I take care only of one of them. In attach crypter free sample with removed AntiVM part so it should work everywhere.
Exactly what kind of anti-* stuff was removed?

I tried the sample under Sandboxie and it aborts execution. I noticed it checks for SbieDll.dll presence, but the DLL is hidden so execution continues after the check, so that´s not what the malware is detecting.
 #12329  by EP_X0FF
 Sun Mar 25, 2012 8:23 am
Buster_BSA wrote:
EP_X0FF wrote:
Maxstar wrote:in a virtual mode there not working.
I assume all three samples are identical, so I take care only of one of them. In attach crypter free sample with removed AntiVM part so it should work everywhere.
Exactly what kind of anti-* stuff was removed?
VM detection (VirtualPC, VBOX, QEMU, VmWare), Wireshark detection, Sandboxie detection.
I tried the sample under Sandboxie and it aborts execution. I noticed it checks for SbieDll.dll presence, but the DLL is hidden so execution continues after the check, so that´s not what the malware is detecting.
if this was this patched binary then it seems checks for sandbox somewhere else additionally.
 #12333  by Buster_BSA
 Sun Mar 25, 2012 10:54 am
EP_X0FF wrote:
Buster_BSA wrote:Exactly what kind of anti-* stuff was removed?
VM detection (VirtualPC, VBOX, QEMU, VmWare), Wireshark detection, Sandboxie detection.
VM detection is discarded as I am running the sample in the host. Sandboxie detection is also discarded because it checks for SbieDll.dll presence and I have it hidden. So probably it´s related to Wireshark detection.

Do you know what is the malware checking for related to Wireshark? WinPCap driver maybe?
EP_X0FF wrote:if this was this patched binary then it seems checks for sandbox somewhere else additionally.
Your patched binary runs fine. I tested the original sample.
 #12334  by EP_X0FF
 Sun Mar 25, 2012 11:12 am
Buster_BSA wrote:Do you know what is the malware checking for related to Wireshark? WinPCap driver maybe?
It looks for presense of "wireshark.exe" in list of running processes.

Additionally this malware is three stage loader.

First - decryption of payload and spawning copy of loader. Second - Vm/Sandboxie/Wshark check and mapping copy of itself to svchost.exe (I assume any). So it can fail here for example, just because it was unable to inject code. Third stage is inside svchost - it's again decryption of real payload with numerous VM/Sandboxie/WShark checks. Patched binary was extracted from 3 stage.
 #12335  by Buster_BSA
 Sun Mar 25, 2012 11:20 am
EP_X0FF wrote:
Buster_BSA wrote:Do you know what is the malware checking for related to Wireshark? WinPCap driver maybe?
It looks for presense of "wireshark.exe" in list of running processes.

Additionally this malware is three stage loader.

First - decryption of payload and spawning copy of loader. Second - Vm/Sandboxie/Wshark check and mapping copy of itself to svchost.exe (I assume any). So it can fail here for example, just because it was unable to inject code. Third stage is inside svchost - it's again decryption of real payload with numerous VM/Sandboxie/WShark checks. Patched binary was extracted from 3 stage.
The problem is in the mapping copy of itselt to svchost.exe. This process is running out of Sandboxie so the injection fails and the malware aborts.

Thank you very much for the information!
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