YARA · WithSecure Labs IOCs

WITHSECURELABS_TEASOUP

Detects common strings found across samples obfuscated with TEASOUP

Suspicious / huntingWithSecure Labs IOCsBSD 2-Clause LicenseCompiles with YARA-X

Author: WithSecure
Date: 2026-05-28
Score / Quality: 75 / 75

What this rule detects

Detects common strings found across samples obfuscated with TEASOUP

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

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

teasoup.yarBSD 2-Clause License

rule WITHSECURELABS_TEASOUP
{
	meta:
		description = "Detects common strings found across samples obfuscated with TEASOUP"
		author = "WithSecure"
		id = "b983f58c-7d53-51d4-b574-1feb8719c2ac"
		date = "2026-05-28"
		modified = "2026-05-28"
		reference = "https://github.com/WithSecureLabs/iocs"
		source_url = "https://github.com/WithSecureLabs/iocs/blob/1a8384468dd292c6d2c5114c32e42dc0da1f5ae1/GREYVIBE/greyvibe.yara#L13-L24"
		license_url = "https://github.com/WithSecureLabs/iocs/blob/1a8384468dd292c6d2c5114c32e42dc0da1f5ae1/LICENSE"
		logic_hash = "357e3d23dac84db54b65ff1727e89eb1dab6e0d06461ebd8368d265c3d1f88bd"
		score = 75
		quality = 75
		tags = ""

	strings:
		$a = "s += String.fromCharCode(charCode)" ascii wide
		$b = "var ts = arr[i]" ascii wide
		$c = "System Maintenance Script" ascii wide

	condition:
		2 of ( $* )
}

Strings (3 patterns)

Identifier	Type	Value	Modifiers
$a	text	"s += String.fromCharCode(charCode)"	ascii wide
$b	text	"var ts = arr[i]"	ascii wide
$c	text	"System Maintenance Script"	ascii wide

Condition

2 of ( $* )

In plain words (Heuristic)

At least 2 patterns in ( $* ) must match.

Test this rule in your browser

Drop a file to scan it with this rule using YARA-X compiled to WebAssembly. Nothing is uploaded.

Drop a file here or click to chooseScanned locally with YARA-X. Files up to 200 MB.

Open in editor

References

https://github.com/WithSecureLabs/iocs

Licence & attribution

Author: WithSecure

Source repository: WithSecure Labs IOCs @ 1a8384468d

Licence: BSD 2-Clause License (repository licence)

Original rule

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

Rule id: b983f58c-7d53-51d4-b574-1feb8719c2ac

WITHSECURELABS_Andariel_Jelusrat_PDB
Suspicious / huntingWithSecure Labs IOCs· WithSecure· 2026-01-22
WITHSECURELABS_LOOKVALJS
Suspicious / huntingWithSecure Labs IOCs· WithSecure· 2026-05-28
WITHSECURELABS_LOOKVALPS
Suspicious / huntingWithSecure Labs IOCs· WithSecure· 2026-05-28
WITHSECURELABS_DAYLIGHT
Suspicious / huntingWithSecure Labs IOCs· WithSecure· 2026-05-28
WITHSECURELABS_Tanglecrypt
Suspicious / huntingWithSecure Labs IOCs· WithSecure· 2025-11-25
WITHSECURELABS_Andariel_Jelusrat_Plugin
MalwareWithSecure Labs IOCs· WithSecure· 2026-01-22
WITHSECURELABS_Ducktail_Nativeaot
MalwareWithSecure Labs IOCs· WithSecure· 2022-11-17
WITHSECURELABS_Andariel_EDR_KILLER_Script
GenericWithSecure Labs IOCs· WithSecure· 2026-01-22