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GCTI_Cobaltstrike_Sleeve_Beaconloader_HA_X86_O_V4_3_V4_4_V4_5_And_V4_6

Cobalt Strike's sleeve/BeaconLoader.HA.x86.o (HeapAlloc) Versions 4.3 through at least 4.6

Hack toolCobalt StrikeGoogle Cloud Threat Intelligence (GCTI)Apache License 2.0Compiles with YARA-X
Author
gssincla@google.com
Date
2022-11-18
Modified
2022-11-19
Score / Quality
75 / 85

What this rule detects

Cobalt Strike's sleeve/BeaconLoader.HA.x86.o (HeapAlloc) Versions 4.3 through at least 4.6

Associated malware family: Cobalt Strike.

It defines 1 patterns (0 text, 1 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

cobaltstrike-sleeve-beaconloader-ha-x86-o-v4-3-v4-4-v4-5-and-v4-6.yarApache License 2.0
rule GCTI_Cobaltstrike_Sleeve_Beaconloader_HA_X86_O_V4_3_V4_4_V4_5_And_V4_6
{
	meta:
		description = "Cobalt Strike's sleeve/BeaconLoader.HA.x86.o (HeapAlloc) Versions 4.3 through at least 4.6"
		author = "gssincla@google.com"
		id = "0ee3fa6f-367c-596f-a3bc-3bcfa61b97aa"
		date = "2022-11-18"
		modified = "2022-11-19"
		reference = "https://cloud.google.com/blog/products/identity-security/making-cobalt-strike-harder-for-threat-actors-to-abuse"
		source_url = "https://github.com/chronicle/GCTI/blob/1c5fd42b1895098527fde00c2d9757edf6b303bb/YARA/CobaltStrike/CobaltStrike__Sleeve_BeaconLoader_all.yara#L17-L59"
		license_url = "https://github.com/chronicle/GCTI/blob/1c5fd42b1895098527fde00c2d9757edf6b303bb/LICENSE"
		hash = "8e4a1862aa3693f0e9011ade23ad3ba036c76ae8ccfb6585dc19ceb101507dcd"
		logic_hash = "d02257bc556d0b1675997ab6af1b28cf5f498855d6254e3c1cd7eb4a0c4d2715"
		score = 75
		quality = 85
		tags = ""

	strings:
		$core_sig = {
      C6 45 F0 48
      C6 45 F1 65
      C6 45 F2 61
      C6 45 F3 70
      C6 45 F4 41
      C6 45 F5 6C
      C6 45 F6 6C
      C6 45 F7 6F
      C6 45 F8 63
      C6 45 F9 00
    }

	condition:
		all of them
}

Strings (1 patterns)

IdentifierTypeValueModifiers
$core_sighex{ C6 45 F0 48 C6 45 F1 65 C6 45 F2 61 C6 45 F3 70 C6 45 F4 41 C6 45 F5 6C C6 45 F6 6C C6 45 F7 6F C6 45 F8 …

Condition

all of them

In plain words (Heuristic)

  • All patterns in the rule must match.

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References

Sample hashes

Hashes of samples the author lists in the rule's meta (look them up in your threat-intelligence platform).

  • 8e4a1862aa3693f0e9011ade23ad3ba036c76ae8ccfb6585dc19ceb101507dcd

Licence & attribution

Author: gssincla@google.com

Source repository: Google Cloud Threat Intelligence (GCTI) @ 1c5fd42b18

Licence: Apache License 2.0 (repository licence)

Original rule

Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.

Rule id: 0ee3fa6f-367c-596f-a3bc-3bcfa61b97aa

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