Adguard Service still downloading website data (e.g. video) after closing browser and saturating net connection

[BooBerry]

https://forum.adguard.com/index.php?threads/adguard-service-still-consumes-bandwidth-after-closing-browser-on-certain-sites.19815/

This is an issue I've noticed for awhile now. On some websites, especially video streaming websites, I've noticed that closing the browser doesn't stop the downloading/streaming of the content until AdguardSvc.exe is killed and restarted. This was an issue some time ago, which was fixed, but it seems to be back in some limited fashion.

In my testing, I used NetBalancer to verify the issue in both on my main machine, along with a clean installed Windows 10 virtual machine with no AV besides Defender. I tried using NetWorx to verify the issue, but it doesn't seem to list non-TCP/IP traffic, which is where it seems this issue is (NetBalancer lists it as Service Traffic being used saturating the entire connection until specifically AdguardSvc.exe is killed).

I used the videos on Swearnet.com (NSFW!) in my testing, as it's the only site I've encountered thus far that causes this issue. There's free videos on the website.

Here's a service log (with debug level logging enabled): http://www.mediafire.com/file/z6a93mvqhwb248i/AdguardServiceLog.zip

Steps to reproduce (I'm using NetBalancer to monitor traffic in real time as it lists Service Traffic, not sure if NetWorx can!):

1. Open NetBalancer's UI and set Down Rate is on top (the process using most down speed appears on top of the list of processes).

2. Open a web browser (used Chrome in my testing, happens with others) and go to swearnet.com

3. Click on Free Video Previews to view any of those videos for free. In my testing, I selected Trailer Park Boys - Trailer Park Boys Podcasts - Podcast Episode 23 - New Year's Regulations which is located here: https://www.swearnet.com/shows/1/seasons/13/episodes/23

4. Let the page load until it's ready for the video to be played.

5. Press the play button, then immediately pause the video so it's downloading/buffering up.

6. Verify the traffic for chrome.exe in NetBalancer's UI window and wait a minute or two.

7. Close the browser - for a moment there's no traffic, then all the sudden Service Traffic spikes and saturates the connection like chrome.exe was while loading the video.

8. Kill AdguardSvc.exe and Service Traffic's connection saturation ends.

And that's it. Running the site with Adguard completely killed results in no issues whatsoever. Adding the site as an exception (both in the user filter and HTTPS exception) doesn't make any difference. Also disabling ad blocking and extensions doesn't make a difference either.

So far swearnet.com is the only site I've encountered where I can reproduce this 100% of the time. I believe there's others out there, but it's hard to reproduce on them.

Good luck with this one!

[ameshkov]

@BooBerry is it specific to a particular driver type?

[BooBerry]

I was able to reproduce it with both the WFP and TDI drivers.

[ameshkov]

Confirmed, fix will arrive soon

[BooBerry]

What exactly is the cause of the issue?

[ameshkov]

This particular case (with closing a browser) was not handled properly:)

[BooBerry]

Any browser? Weird, this issue should be more apparent on other sites, especially videos.

[ameshkov]

Yeah, I am surprised as well. Maybe people don't tend to close browser that often?

[BooBerry]

I do, a lot. But I was noticing for awhile now my internet connection would be in use (when nothing should be actively using it). I turned off automatic Windows updates and Store updates, and still it'd happen sometimes. It wasn't until I began visiting that site I'd really notice it.

I bet it's not limited to streaming videos either, anything in the middle of an established, ongoing connection would continue (indefinitely?).

IMO, it might be a high to critical type of issue. =P

[ameshkov]

Is it easy to reproduce on other websites, like YT for instance? I have used the same website for tests and start thinking, that this issue might be also caused by the way the server behaves.

[BooBerry]

I couldn't reproduce it on YT in my testing. Sometimes it'd happen with Facebook videos, I found. But it wasn't consistent at all.

Only Swearnet seems to be consistent. That site seems actually pretty slow when loading videos. My internet connection may be slow, but I can stream YT at 720p with no issues with buffering. Swearnet seems to be different, it chokes when buffering video, even at 360p and 480p. In fact, I've noticed when buffering video download traffic actually stops for a few seconds then resumes at full speed. In addition to that, sometimes if I hit the point where it begins to buffer and don't press pause fast enough, the playback will actually start back from the beginning again. It's rather annoying on that site.