Firefox crashes in the Containment

Recently tried to run Firefox (76.0.1) in the Containment and it crashes. I tried with Firefox with add-ons disabled but that didn’t help. Also I changed the settings to allow startup for services installed in the container and to allow application access to the clipboard with to no avail. However MS Edge is running just fine in the Containment.

I am using Windows 8.1 x64 and Comodo Firewall

Any ideas? Thanks!

V12.2.2.7036 (Firewall only) Windows 7 Ultimate 64-bit

I just installed Firefox V76.0.1 on my system to try it out running in containment.
On my system it does start and runs in containment without problems (however no add-ons, just plain Firefox).

Hello B-boy/StyLe/,

Thank you for reporting.Could you please check your CIS folder and if you found any crash dump in the sense kindly share.
Have a nice day.

Hi CISfan,

Thanks for testing it for me!

Hi Dharshu,

Unfortunately there is no crash dmp files in the CIS folder (only one but not related to the current issue):

And I can’t copy the details outside the sandbox: (maybe I should enable the option that allow application access to the clipboard again to do that)

Yeah, you probably noticed the Kaspersky library in the mix and yes I am using Kaspersky Security Cloud Free (but so far didn’t encounter any compatibility issues between Kaspersky and Comodo). Also I disabled Kaspersky for the test but Mozilla crashed again in the Containment. And yes I tried with the latest version from a few days ago - 77.0.1.

And one more thing. Why when I am opening Adobe Acrobat DC in the Containment there is no green borders around it? But when I use File => Open then I can see the green borders around the new window?


Have you tried to “Containment Tasks->Reset the Container” first and then run Firefox contained again? Does it still crash then?


I already tried this out. I double-checked and the folder C:\VTRoot was gone but with no success.


When you start Firefox in containment do you see the normal Firefox window first and then the Crash Reporter Window popping up?
Or does Firefox window not open at all and only Crash Reporter Window pops up?

Unfortunately FF doesn’t open at all. It is crashing directly upon start up.

Btw the pagefile is moved to another drive since I am using SSD. Can this be the reason for this issue? I will move it back to C:\ to test this out.

Just for my understanding, I assume Firefox runs uncontained normally so without crashing?

Yes, when not in the Containment FF is running stable and smoothly. :slight_smile:

Your going to need to navigate the vtroot folder to find the crash dump, you need to look in %USERPROFILE%
appdata\local\crashdumps both in vtroot and real location for firefox memory dumps.

Ok as I said earlier there is no crash dmp files in the default FF folders but I forgot to check the C:\VTRoot folder. Now I found 2 files (with different timestamp and size) so I am zipping them both:

And one more thing (not related to the current issue). The diagnostic utility failed to complete (the problem started a few weeks ago). I checked the log and I noticed the following:

Why is that happening?


Hello B-boy/StyLe/,

Diagnostic Error : It’s an known issue and our CIS team are checking in it.It will be fixed and reflecting in the upcoming release.
Have a nice day!

Disabling Kaspersky won’t matter if its dll is still being injected into every launched process, I would try renaming the dll so it doesn’t get injected when you run firefox in containment. If firefox still crashes then it can be an issue with a filesystem filter driver which you can list using fltmc from an elevated command prompt.


Yes, renaming the file C:\ProgramData\Kaspersky Lab\AVP20.0\Bases\klsihk64.dll (for the testing purpose did the trick). I stopped the Self-Defense of Kaspersky first. Now Firefox starts in the Containment without any errors. It seems that Kaspersky don’t inject into edge exe regarding Process Explorer. Maybe MS is blocking unauthorized code injection in Edge? But the article below is valid for the legacy version of Edge probably (and not for the Chromium one?) and Windows 10 (I am using 8.1 still).

A solution would be to ask Mozilla (Firefox) to add the offending dll to their blocklist to prevent the dll from being injected into their Firefox process. Be ware: Whatever functions the dll tries to accomplish in Firefox, you will lose those functionalities then. But the same happens in Edge when MS is blocking it too.

Firefox is actively blocking dll injections into their process to improve Firefox stability and to increase the security level so I think they will add it to their blocklist if need be.

The issue seems to be resolved since Kaspersky Security Cloud Free doesn’t seems to use klsihk64.dll anymore.