/* Yara Rule Set Author: Florian Roth Date: 2017-07-15 Identifier: CHAOS Reference: https://github.com/tiagorlampert/CHAOS */ /* Rule Set ----------------------------------------------------------------- */ rule CHAOS_Payload { meta: description = "Detects a CHAOS back connect payload" license = "https://creativecommons.org/licenses/by-nc/4.0/" author = "Florian Roth" reference = "https://github.com/tiagorlampert/CHAOS" date = "2017-07-15" score = 80 hash1 = "0962fcfcb1b52df148720c2112b036e75755f09279e3ebfce1636739af9b4448" hash2 = "5c3553345f824b7b6de09ccb67d834e428b8df17443d98816471ca28f5a11424" strings: $x1 = { 2F 43 48 41 4F 53 00 02 73 79 6E 63 2F 61 74 6F 6D 69 63 } condition: ( uint16(0) == 0x5a4d and filesize < 15000KB and all of them ) }