Avast is useless against certain types of virus

Avast Free Antivirus / Premium Security
1

Yes, avast completely ignores viruses written in obfuscated javascript/vbscript code.
I get several of these every week and avast lets them all through.
This is a SEVERE issue that should be solved ASAP.

Want examples?
Here:

https://www.virustotal.com/#/file/a3dd786627949debaface405180f9b6f399f249ef7e44727d1beabd80f841a12/detection
https://www.virustotal.com/#/file/05d2594afe49c6ef2032dc9b7dd73a2a5cdb1a068415e957b7e62ed2a82679a5/detection

etc.
I’ve got hundreds of those…
This BBS won’t let me upload the files. too bad.

2

I managed to de-obfuscate one of the files using www.jsnice.org and even after decoding it, avast still doesn’t detect anything.

virus total on the decoded file:

https://www.virustotal.com/es/file/bdd7311152133110575dae23fabe05e04e199e41162999adaf5656a12629922c/analysis/1522868532/

3

Hi! You can always send/Reporting malware samples to the Avast Threat Lab:https://www.avast.com/report-malicious-file.php

Yes, I am agree with you.Avast is weak against viruses written in obfuscated javascript/vbscript code.

4

I would die of old age if I start sending all the samples of viruses undetected by avast…

5

Use ZIP File and send them all to avast or if you are unable to use the submission form, attach the file to an email and send it to submit@virus.avast.com with the subject line Undetected Malware.

6

Reporting malware samples to the Avast Threat Lab: https://support.avast.com/article/258/

7

Samples will be detected in upcoming VPS update.
Thank you for report !

8

Is there any chance of protection improvement against viruses written in obfuscated javascript/vbscript code?

9

In general obfuscated scripts are most likely to be detected during execution time after AMSI takes action. Just like other detections that happens at execution time those won’t show up on Virustotal.

Note that AMSI is only available on Windows 10 - https://cloudblogs.microsoft.com/microsoftsecure/2015/06/09/windows-10-to-offer-application-developers-new-malware-defenses/

10

Should I still submit samples or you guys have it covered?

11

You should submit undetected samples to avast viruslab.

12

Is there any chance of improvement against viruses written in obfuscated javascript/vbscript code in future versions of avast antivirus?.For now Avast is weak.