…according to a Twitter post by the Chief Informational Security Officer of Grand Canyon Education.
So, does anyone else find it odd that the file that caused everything CrowdStrike to freak out, C-00000291-
00000000-00000032.sys was 42KB of blank/null values, while the replacement file C-00000291-00000000-
00000.033.sys was 35KB and looked like a normal, if not obfuscated sys/.conf file?
Also, apparently CrowdStrike had at least 5 hours to work on the problem between the time it was discovered and the time it was fixed.
Yeah pretty much all security products need kernel level access unfortunately. The Linux ones including crowdstrike and also the Open Source tools SELinux and AppArmor all need some kind of kernel module in order to work.
crowdstrike has caused issues like this with linux systems in the past, but sounds like they have now moved to eBPF user mode by default (I don’t know enough about low level linux to understand that though haha), and it now can’t crash the whole computer. source
As explained in that source eBPF code is still running in kernel space. The difference is it’s not turing complete and has protections in place to make sure it can’t do anything too nasty. That being said I am sure you could still break something like networking or critical services on the system by applying the wrong eBPF code. It’s on the authors of the software to make sure they thoroughly test and review their software prior to release if it’s designed to work with the kernel especially in enterprise environments. I am glad this is something they are doing though.
At least SELinux doesn’t crash on bad config file
I am not praising crowdstrike here. They fucked up big time. I am saying that the concept of security software needing kernel access isn’t that unheard of, and is unfortunately necessary for a reason. There is only so much a security thing can do without that kernel level access.