Skip to content

YARA · SEKOIA.IO Community

SEKOIA_Loader_Win_Jinxloader_Strings

Finds JinxLoader samples based on the specific strings

MalwareJinxloaderSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X
Author
Sekoia.io
Date
2023-12-04
Modified
2024-12-19
Score / Quality
75 / 80

What this rule detects

Finds JinxLoader samples based on the specific strings

Associated malware family: Jinxloader.

Targets: Windows PE.

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

Summary generated from the rule's metadata and condition.

Rule source

loader-win-jinxloader-strings.yarDetection Rule License 1.1
rule SEKOIA_Loader_Win_Jinxloader_Strings : FILE
{
	meta:
		description = "Finds JinxLoader samples based on the specific strings"
		author = "Sekoia.io"
		id = "fd2f7e8c-f4a8-4452-bbc6-e03790f8ed89"
		date = "2023-12-04"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/loader_win_jinxloader_strings.yar#L1-L20"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "816cb6019cba1aa2e229ab476fcdf378348981920cbe17d3dfb875f8b2dcbf81"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$str01 = "JinxV2" ascii
		$str02 = "main.main.func1" ascii
		$str03 = "go.shape.struct" ascii
		$str04 = ".glob..func" ascii

	condition:
		uint16( 0 ) == 0x5A4D and all of them and #str04 > 100 and filesize > 8MB
}

Strings (4 patterns)

IdentifierTypeValueModifiers
$str01text"JinxV2"ascii
$str02text"main.main.func1"ascii
$str03text"go.shape.struct"ascii
$str04text".glob..func"ascii

Condition

uint16( 0 ) == 0x5A4D and all of them and #str04 > 100 and filesize > 8MB

In plain words (Heuristic)

  • The file must start with “MZ” — a Windows executable (PE).
  • The file must be larger than 8MB.
  • All patterns in the rule must match.
  • Pattern $str04 must occur > 100 times.

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: fd2f7e8c-f4a8-4452-bbc6-e03790f8ed89

Metadata

version1.0
classificationTLP:CLEAR

Tags:FILE

More Jinxloader rules