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SIGNATURE_BASE_HKTL_Cobaltstrike_Beacon_Strings

Identifies strings used in Cobalt Strike Beacon DLL

Hack toolCobalt StrikeSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X
Author
Elastic
Date
2021-03-16
Modified
2026-05-26
Score / Quality
75 / 85

What this rule detects

Identifies strings used in Cobalt Strike Beacon DLL

Associated malware family: Cobalt Strike.

It defines 3 patterns (3 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar
hktl-cobaltstrike-beacon-strings.yarDetection Rule License 1.1
rule SIGNATURE_BASE_HKTL_Cobaltstrike_Beacon_Strings
{
	meta:
		description = "Identifies strings used in Cobalt Strike Beacon DLL"
		author = "Elastic"
		id = "af558aa2-a3dc-5a7a-bc74-42bb2246091c"
		date = "2021-03-16"
		modified = "2026-05-26"
		reference = "https://www.elastic.co/blog/detecting-cobalt-strike-with-memory-signatures"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/apt_cobaltstrike.yar#L54-L67"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		logic_hash = "4349a7ad94df2269217b55c2aef9628c4eef078566c276936accdd4f996ba2cf"
		score = 75
		quality = 85
		tags = ""

	strings:
		$s1 = "%02d/%02d/%02d %02d:%02d:%02d"
		$s2 = "Started service %s on %s"
		$s3 = "%s as %s\\%s: %d"

	condition:
		2 of them
}

Strings (3 patterns)

IdentifierTypeValueModifiers
$s1text"%02d/%02d/%02d %02d:%02d:%02d"
$s2text"Started service %s on %s"
$s3text"%s as %s\\%s: %d"

Condition

2 of them

In plain words (Heuristic)

  • At least 2 patterns in the rule must match.

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References

Licence & attribution

Author: Elastic

Source repository: Signature Base (Florian Roth / Nextron) @ 94a1c48d7a

Licence: Detection Rule License 1.1 (repository licence)

Original rule

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

Rule id: af558aa2-a3dc-5a7a-bc74-42bb2246091c

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