CobaltStrike_Resources_Beacon_x64_v3_3

rule CobaltStrike_Resources_Beacon_x64_v3_3
{
  meta:
    description = "Cobalt Strike's sleeve/beacon.x64.dll Versions 3.3"
    hash =  "7b00721efeff6ed94ab108477d57b03022692e288cc5814feb5e9d83e3788580"
		author = "gssincla@google.com"
		reference = "https://cloud.google.com/blog/products/identity-security/making-cobalt-strike-harder-for-threat-actors-to-abuse"
		date = "2022-11-18"
    
    id = "fb96ecff-809e-5704-974e-a2d8ef022daa"
  strings:
    /*
      8B D3                mov     edx, ebx
      48 8B CF             mov     rcx, rdi
      E8 89 66 00 00       call    sub_1800155E8
      E9 23 FB FF FF       jmp     loc_18000EA87
      41 B8 01 00 00 00    mov     r8d, 1
      E9 F3 FD FF FF       jmp     loc_18000ED62
      48 8D 0D 2A F8 FF FF lea     rcx, sub_18000E7A0
      E8 8D 2B 00 00       call    sub_180011B08
      48 8B 5C 24 30       mov     rbx, [rsp+28h+arg_0]
      48 83 C4 20          add     rsp, 20h
    */

    $version_sig = { 8B D3 48 8B CF E8 89 66 00 00 E9 23 FB FF FF 
                     41 B8 01 00 00 00 E9 F3 FD FF FF 48 8D 0D 2A F8 FF FF
                     E8 8D 2B 00 00 48 8B 5C 24 30 48 83 C4 20 }

    /*
      80 31 ??          xor     byte ptr [rcx], 69h
      FF C2             inc     edx
      48 FF C1          inc     rcx
      48 63 C2          movsxd  rax, edx
      48 3D 10 06 00 00 cmp     rax, 610h
    */

    $decoder = { 80 31 ?? FF C2 48 FF C1 48 63 C2 48 3D 10 06 00 00 }
    
  condition:
    all of them
}