Insomni'hack 2025: de-obfuscating strings in Linux/RudeDevil

by cryptax
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GNU/Linux • xterm-256color • bash 482 views

Using r2ai, we decompile the main of RudeDevil. We verify the cryptocurrency address is not a hallucination, nor function EncryptData. Then, we see the arguments passed to EncryptData: an encrypted buffer, a buffer length and a key. We ask the AI to write a Python script to decrypt the strings. We verify and edit the script the AI wrote: there were a few errors on how to display the decrypted strings. We run the script on our host and get the decrypted string value (a malicious URL).

This concerns a malicious sample of Linux/RudeDevil of February 2025.

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