Kaspersky has answered on bugzilla:

"It is our (Kaspersky) fault. We have “anti-cryptor” feature, which can safe user files, if malicious software crypt it.
There were bug in this feature...

No VPN here, BSOD only when using Firefox 57.x

just tested, doesn't work for me. still blue screen after few minutes using Firefox 57. I think the bug is in Firefox 57. Do not recognize a connection to Kaspersky

just download and install Firefox 56.0.2 This is the latest version that works fine without causing a blue screen. You must only disable updates.
I will wait for a new firefox update until this...

Exactly same here! Since update to Firefox 57.0.x I get bluescreens after closing Firefox Windows, closing Tabs or watching youtube videos:
kmode_exception_not_handled (classpnp.sys)
I'm going...