Avast Pro fails to recognize outdated trojan

Recently I contacted Avast support about a trojan threat it failed to stop. Below is my message and their reply. I was satisfied with Avast prior to this incident but now I’m thinking that if support is right and only one security program should be running, perhaps it should be Microsoft Security Essentials. Anyone else experience a similar issue with Avast and would you find this response acceptable?


While on the net I received an alert from Microsoft Security Essentials saying it had blocked a trojan. I wasn’t aware MSE was even enabled as I rely only on Avast and Malwarebytes for security. Luckily MSE was activated as the alert stated the trojan threat was ‘severe.’

According to Microsoft’s site, this malware has been around for a couple of years so Avast should have detected it. Can you explain why there was no warning and why a free program seemingly offers greater protection than Avast Pro?

Trojandownloader: ASX/Wimad.AN 9/10/2011 3:00 PM Action Taken: Removed

Avast reply:

We don´t recommend to use two or more security programs at the same time. It can cause many problems and the operating system may become unstable. Also the results of virus scan can be affected.

We are adding new virus samples every day, but it is true that we may miss some spyware and adware threats. So if you have something avast is missing, please send the file(s) to virus@avast.com for analysis.

first, no security program have 100% detection…

here it is detecting one version
http://www.virustotal.com/file-scan/report.html?id=b51dca764dee7fc6eb57a1bb9eafdf7c0a34cd121b83dfdd437cf340b346757f-1310943243

second, how do you know this is not a False Positive as a result of having two AV programs installed ?
you cant just deactivate, you need to uninstall…

Never install two antivirus (see reply from quietman7)
http://www.bleepingcomputer.com/forums/index.php?s=7c8217673a726b92cfc91ecfd4294a29&showtopic=260844&view=findpost&p=1441638

run and reboot - Uninstallers for Security Software
http://thewebatom.net/uninstallers/security-software/

upload suspicious file(s) to www.virustotal.com and test with 43 malware scanners
when you have the result, copy the url in the address bar and post it here for us to see

alternative
Jotti http://virusscan.jotti.org/en
VirSCAN http://virscan.org/
Metascan http://www.metascan-online.com/

Appreciate the advice Pondus. The suspected file was already removed by MSE and my PC is clean now but judging from the report the program and the MS site gave at the time, it appears the threat was legitimate. The other thing that makes me think it wasn’t a false positive is that it happened right after I replied to a tweet and a comment that seemed designed to solicit strong opposition. At any rate, I’ll give Avast the benefit of the doubt for now and run with just the one security app. No more tweeting either! ;D

Category: Trojan Downloader: ASX/Wimad.AN

Alert level: Severe Action: Removed

Description: This program is dangerous and downloads other programs.

Recommended action: Remove this software immediately.