Skip to content

YARA · SEKOIA.IO Community

SEKOIA_Tool_Powershell_Unicorn

Detects Unicorn Powershell

Hack toolUnicornSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X
Author
Sekoia.io
Date
2022-08-23
Modified
2024-12-19
Score / Quality
75 / 80

What this rule detects

Detects Unicorn Powershell

Associated malware family: Unicorn.

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

Summary generated from the rule's metadata and condition.

Rule source

tool-powershell-unicorn.yarDetection Rule License 1.1
rule SEKOIA_Tool_Powershell_Unicorn : FILE
{
	meta:
		description = "Detects Unicorn Powershell"
		author = "Sekoia.io"
		id = "287c1669-2ee1-488e-bf66-a99bfe309c90"
		date = "2022-08-23"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/tool_powershell_unicorn.yar#L1-L17"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "8be79789cf77d4f304d9fef4ad6a2d2ac7686b015fff3301fb3e369f2f06230a"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = ").value.toString() ('JAB" ascii wide
		$ = ").value.toString());powershell (" ascii wide
		$ = "powershell /w 1 " ascii wide

	condition:
		all of them and filesize < 100KB
}

Strings (3 patterns)

IdentifierTypeValueModifiers
$text").value.toString() ('JAB"ascii wide
$text").value.toString());powershell ("ascii wide
$text"powershell /w 1 "ascii wide

Condition

all of them and filesize < 100KB

In plain words (Heuristic)

  • The file must be smaller than 100KB (a cheap guard that skips large files).
  • All patterns in the rule 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

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: 287c1669-2ee1-488e-bf66-a99bfe309c90

Metadata

version1.0
classificationTLP:CLEAR

Tags:FILE