rule SUSP_RANSOMWARE_Indicator_Jul20 { meta: description = "Detects ransomware indicator" author = "Florian Roth (Nextron Systems)" reference = "https://securelist.com/lazarus-on-the-hunt-for-big-game/97757/" date = "2020-07-28" score = 60 hash1 = "52888b5f881f4941ae7a8f4d84de27fc502413861f96ee58ee560c09c11880d6" hash2 = "5e78475d10418c6938723f6cfefb89d5e9de61e45ecf374bb435c1c99dd4a473" hash3 = "6cb9afff8166976bd62bb29b12ed617784d6e74b110afcf8955477573594f306" id = "6036fdfd-8474-5d79-ac75-137ac2efdc77" strings: $ = "Decrypt.txt" ascii wide $ = "DecryptFiles.txt" ascii wide $ = "Decrypt-Files.txt" ascii wide $ = "DecryptFilesHere.txt" ascii wide $ = "DECRYPT.txt" ascii wide $ = "DecryptFiles.txt" ascii wide $ = "DECRYPT-FILES.txt" ascii wide $ = "DecryptFilesHere.txt" ascii wide $ = "DECRYPT_INSTRUCTION.TXT" ascii wide $ = "FILES ENCRYPTED.txt" ascii wide $ = "DECRYPT MY FILES" ascii wide $ = "DECRYPT-MY-FILES" ascii wide $ = "DECRYPT_MY_FILES" ascii wide $ = "DECRYPT YOUR FILES" ascii wide $ = "DECRYPT-YOUR-FILES" ascii wide $ = "DECRYPT_YOUR_FILES" ascii wide $ = "DECRYPT FILES.txt" ascii wide condition: uint16(0) == 0x5a4d and filesize < 1400KB and 1 of them }