Work hard in silence , let success make the noise.
Apr 23, 2021 • 4 tweets • 3 min read
Diving into the #Lazarus sample that mentioned in nice blog tinyurl.com/mdyxr8m3. I recognized it uses 2 custom algorithms for decoding strings.
- 1st is modified RC4 to decrypt API functions name.
- 2nd is custom algo to decrypt C2 urls and user agent strings (1/4)
For decrypting API functions name, it decode base64 string and call modified rc4 algo to decrypt the decoded base64 string (2/4).