import "hash" rule CrossRAT: RAT { meta: description = "Detects CrossRAT known hash" author = "Simon Sigre (simon.sigre@gmail.com)" date = "26/01/2018" ref = "https://simonsigre.com" ref= "https://objective-see.com/blog/blog_0x28.html" strings: $magic = { 50 4b 03 04 ( 14 | 0a ) 00 } $string_1 = "META-INF/" $string_2 = ".class" nocase condition: filesize < 400KB and $magic at 0 and 1 of ($string_*) and hash.md5(0, filesize) == "85b794e080d83a91e904b97769e1e770" }