YARA · SEKOIA.IO Community

SEKOIA_Apt_Gelsemium_Wolfsbane_Launcher

Detects Gelsemium's WolfsBane launcher

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

Author: Sekoia.io
Date: 2024-11-22
Modified: 2024-12-19
Score / Quality: 75 / 80

What this rule detects

Detects Gelsemium's WolfsBane launcher

Targets: Linux ELF.

It defines 4 patterns (4 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

apt-gelsemium-wolfsbane-launcher.yarDetection Rule License 1.1

rule SEKOIA_Apt_Gelsemium_Wolfsbane_Launcher : FILE
{
	meta:
		description = "Detects Gelsemium's WolfsBane launcher"
		author = "Sekoia.io"
		id = "26fbf4df-aa08-47b6-a73c-e8f80a408454"
		date = "2024-11-22"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/apt_gelsemium_wolfsbane_launcher.yar#L1-L21"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		hash = "87e437cf74ce4b1330b8af9ff71edae2"
		logic_hash = "9ecc3a8cb82f6183c263dde03a14f721d2e3aeb2338afc28e0368c323e5d51a9"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = "rm -f /dev/shm/sem*%s"
		$ = "/etc/ld.so.preload"
		$ = "kill -9 %d 2>/dev/null"
		$ = "/,1d' %s 2>/dev/null"

	condition:
		uint32be( 0 ) == 0x7F454C46 and filesize < 500KB and all of them
}

Strings (4 patterns)

Identifier	Type	Value
$	text	"rm -f /dev/shm/sem*%s"
$	text	"/etc/ld.so.preload"
$	text	"kill -9 %d 2>/dev/null"
$	text	"/,1d' %s 2>/dev/null"

Condition

uint32be( 0 ) == 0x7F454C46 and filesize < 500KB and all of them

In plain words (Heuristic)

The file must start with the ELF header — a Linux/Unix executable.
The file must be smaller than 500KB (a cheap guard that skips large files).
All patterns in the rule must match.

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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).

87e437cf74ce4b1330b8af9ff71edae2

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: 26fbf4df-aa08-47b6-a73c-e8f80a408454

Metadata

version	1.0
classification	TLP:CLEAR

Tags:FILE

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