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Conversation

Sajid Nawaz Khan

Probably the most comprehensive Regex I’ve seen yet to identify Log4Shell exploitation attempts: github.com/back2root/log4 #CVE-2021-44228 #Log4j

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Okay, I love regex, but maybe it's not the right tool for this job. Case in point, look at that god damned regex. Do I understand it? Sure. Do I think it's a good idea in this situation? God no. Will it work? Ah hell, it might, but trying to debug that thing is... no.

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It is though. If you can identify an exploit sequence with a type 3 language you shouldn't unnecessarily involve a type 0 one. That regex will surely run in O(n) time. Your 100 line program code? possibly not, maybe it never even terminates.

4:32 PM · Dec 18, 2021