YARA · SEKOIA.IO Community

SEKOIA_Apt_Kimsuky_Toddlershark_Strings

Detects Kimsuky TODDLERSHARK vbs malware

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

Author: Sekoia.io
Date: 2024-03-06
Modified: 2024-12-19
Score / Quality: 75 / 80

What this rule detects

Detects Kimsuky TODDLERSHARK vbs malware

Associated malware family: Kimsuky.

It defines 6 patterns (6 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

apt-kimsuky-toddlershark-strings.yarDetection Rule License 1.1

rule SEKOIA_Apt_Kimsuky_Toddlershark_Strings : FILE
{
	meta:
		description = "Detects Kimsuky TODDLERSHARK vbs malware"
		author = "Sekoia.io"
		id = "2db1a424-9e83-4168-8ebf-d3b415b6a576"
		date = "2024-03-06"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/apt_kimsuky_toddlershark_strings.yar#L1-L20"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "dee9d03f498437dd6d8399975cd91ec44307067ac4642b9ff31df1a6d6b10468"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = "On Error Resume Next"
		$ = ".open \"POST\", \"http"
		$ = ".setRequestHeader"
		$ = ".send"
		$ = "Execute("
		$ = ".responseText)"

	condition:
		all of them and filesize < 450
}

Strings (6 patterns)

Identifier	Type	Value
$	text	"On Error Resume Next"
$	text	".open \"POST\", \"http"
$	text	".setRequestHeader"
$	text	".send"
$	text	"Execute("
$	text	".responseText)"

Condition

all of them and filesize < 450

In plain words (Heuristic)

The file must be smaller than 450 (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

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: 2db1a424-9e83-4168-8ebf-d3b415b6a576

Metadata

version	1.0
classification	TLP:CLEAR

Tags:FILE

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