New Member

Avast released its 2015 lineup recently and one of the new features that all of its antivirus programs ship with is HTTPS Scanning.

It enables the program to detect and decrypt protected traffic using its web filtering component. This alone is highly problematic considering that the program is tapping right into protected data streams but the current implementation is causing all kinds of issues on top of that.

Firefox users for example may notice that the browser won't close anymore because of Avast's HTTPS Scanning feature. This may not happen all the time when Firefox is closed but users reported that it is happening frequently.

That's however not the only issue that Firefox users may experience if Avast is installed on the computer system the browser is running on.

Firefox's add-on update check may be blocked by the security software as well.

The Mozilla Firefox web browser is not the only program that is affected by issues though. Spotify's Web Player may not be able to connect to Spotify for example with Avast 2015 running on the system.

avast! Protection

New Member
As I can see, there's an update of the article stating that the latest update of Avast or Firefox has fixed the issue. :)

The Spotify's Web Player issue addressed in this article is a week old. So if someone has this app, please check if the problem is patched.

With the time, all these bugs will be fixed anyway. It just takes some time to find them and submit them to Avast..
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Staff member
FYI: Windows XP and Vista users are not affected, since HTTPS Scanning is not available for older OSes.

Is avast! scanning the HTTPS data streams, a conflict in privacy and/or security?

avast! Protection

New Member
Personally, I think there are more advantages than disadvantages.

The HTTPS scanning option is just another security layer. Avast places its own client-side certificate for all traffic coming through the 443 (SSL) port thus meaning that Avast will scan everything coming through that port. If the HTTPS scanning option is turned off, Avast users will rely on the File System Shield to detect or not a given sample as malware.

You can see it in action with the "EICAR" test virus -

Play with the HTTPS Scanning option and try to download the file via the secured https download link.

More about the EICAR anti-malware test file:
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Tony Cole

Level 27
Thanks for the info, I didn't realize https scanning would work in Google Chrome. Is there any info to suggest it would block certain actions within Chrome?

I've just tried to download EICAR via https and it was instantly blocked by avast! premier. I have not messed around with any settings, so avast! is on default settings. EICAR (via https) was instantly blocked before the file could be downloaded.

There is no need to change any settings, as default blocks all :)