I realized it doesn’t matter which source the downloaded file comes from. It always gets cancelled.
Now if this is a wanted behaivor from avast! AV i have to say it doesn’t make any sense.
If i choose to disable the On-Access-Protection for some reason it shouldn’t matter that i download something right now. It’s risky anyway to disable the shield, and it wouldn’t make any difference in the end, because i can still disable the On-Access-Protection and THEN download a file without it being scanned. Result: Same risk as before.
I don’t think it’s a bug. Webshield works like a proxy and it’s monitoring the traffic being downloaded, disabling it is disconnect that particular traffic…
Web > Web Shield > Browser > Standard Shield
All data is first checked and then passed to the browser, and if the data is cached it can be also checked by Standard Shield.
While you are performing a download (or any http access) with the Webshield active the Webshield actually becomes your browser since it (not your browser) is the function performing the download.
So this is really like saying “I turned off my bowser in the middle of the download and the download did not complete”.
This is the way the Webshield has worked in avast ever since it was introduced - the Webshield did not change in 4.8.1169.
Yea i get that, but other AV-products work similar to this and don’t interrupt any downloads.
The problem is, why would avast! AV check a file, until it is fully downloaded? At least that’s how i understand the behaivor of a proxy, if not it would have to check every file bit by bit on-the-fly right? This would take alot of cpu-ressources etc. which could be avoided, because why would an AV do that with a file, that can’t be executed already in the first place? It’s not more secure than checking a file that was fully downloaded and then executed or whatever.
Correct me if i’m wrong, but i don’t really get the logic right now.
Downloading the file fully, then scanning it, and then passing it to the browser gives you quite bad browsing exprience. You don’t see the page being loaded progressively - you have to wait for half a minute or so, without getting a small bit, and then the whole page appears.
So, what you are describing is basically the behavior when the option “Use intelligent stream scanning” is disabled in WebShield.
As alanrf said, WebShield has always worked like this… it hasn’t changed in 4.8. lukor might have some more info, but I don’t think this is going to change.
Believe us… this is a feature that not all other antivirus have.
Scanning the http traffic avast blocks the malware even before the file is saved in your computer.
WebShield scans the traffic on-the-fly, is does not take a lot of resources.
Even with the Intelligent stream scanning disabled, your downloads would be terminated, when the downloading process - WebShield - is terminated. The only possibility might be to “schedule” the stop and wait with it until all downloads are completed … hmm, but since it is this way for several years I don’t know if this feature is so important.
