YARA · SEKOIA.IO Community

SEKOIA_Apt_Lazarus_Backdoored_Jslib

Detects InvisibleFerret based on common ressource.

APT / threat actorSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X

Author: Sekoia.io
Date: 2024-10-28
Modified: 2024-12-19
Score / Quality: 75 / 80

What this rule detects

Detects InvisibleFerret based on common ressource.

It defines 2 patterns (2 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

apt-lazarus-backdoored-jslib.yarDetection Rule License 1.1

rule SEKOIA_Apt_Lazarus_Backdoored_Jslib : FILE
{
	meta:
		description = "Detects InvisibleFerret based on common ressource."
		author = "Sekoia.io"
		id = "73ffd449-93c8-494e-9c14-2e933b21a200"
		date = "2024-10-28"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/apt_lazarus_backdoored_jslib.yar#L1-L17"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		hash = "52e92be527690f4e63608cbc699e2f70"
		logic_hash = "205ad321afcb22ae2bf6cf2a58ce970ea9b0edda7fab60ddeda5ea36ecfe3cb9"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$obf = "(function(_0x" ascii
		$exp = "module.exports =" ascii

	condition:
		$exp in ( filesize -500 .. filesize ) and #obf == 1
}

Strings (2 patterns)

Identifier	Type	Value	Modifiers
$obf	text	"(function(_0x"	ascii
$exp	text	"module.exports ="	ascii

Condition

$exp in ( filesize -500 .. filesize ) and #obf == 1

In plain words (Heuristic)

Pattern $obf must occur == 1 times.
Pattern $exp must be found within the range filesize -500 .. filesize.

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References

https://github.com/SEKOIA-IO/Community

Sample hashes

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

52e92be527690f4e63608cbc699e2f70

Licence & attribution

Author: Sekoia.io

Source repository: SEKOIA.IO Community @ a438a5901a

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: 73ffd449-93c8-494e-9c14-2e933b21a200

Metadata

version	1.0
classification	TLP:CLEAR

Tags:FILE

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