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YARA · Signature Base (Florian Roth / Nextron)

SIGNATURE_BASE_Crime_Win32_Parallax_Loader_1

Detects Parallax Loader

MalwareParallaxSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X
Author
@VK_Intel
Date
2020-02-24
Modified
2023-12-05
Score / Quality
75 / 85

What this rule detects

Detects Parallax Loader

Associated malware family: Parallax.

Targets: Windows PE.

It defines 2 patterns (0 text, 2 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar
crime-win32-parallax-loader-1.yarDetection Rule License 1.1
rule SIGNATURE_BASE_Crime_Win32_Parallax_Loader_1 : FILE
{
	meta:
		description = "Detects Parallax Loader"
		author = "@VK_Intel"
		id = "5e030b68-3c29-5203-bb4e-f01850bfbbab"
		date = "2020-02-24"
		modified = "2023-12-05"
		reference = "https://twitter.com/VK_Intel/status/1227976106227224578"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/crime_parallax_rat.yar#L2-L18"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		hash = "829fce14ac8b9ad293076c16a1750502c6b303123c9bd0fb17c1772330577d65"
		logic_hash = "1331e7b69fd9b14b5d2dae45b452b385e48018290d91de33a4f4a5ebcce4805b"
		score = 75
		quality = 85
		tags = "FILE"

	strings:
		$main_call = { 68 81 85 50 00 e8 ?? ?? ?? ?? 89 ?? ?? ?? ?? ?? 8d ?? ?? ?? ?? ?? 51 ff ?? ?? ?? ?? ?? e8 ?? ?? ?? ?? 89 ?? ?? ?? ?? ?? ff ?? ?? ?? ?? ?? 68 00 10 00 00 68 b0 a2 00 00 ff ?? ?? ?? ?? ?? ff ?? ?? ?? ?? ?? 89 ?? ?? ?? ?? ?? ff ?? ?? ?? ?? ?? 68 8c e1 4f 00 ff ?? ?? ?? ?? ?? e8 ?? ?? ?? ?? 83 c4 0c 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 89 ?? ?? 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 89 ?? ?? 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 89 ?? ?? 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 89 ?? ?? 8b ?? ?? ?? ?? ?? 03 ?? ?? ?? ?? ?? 89 ?? ?? ?? ?? ?? 8b ?? ?? ?? ?? ?? 89 ?? ?? ?? ?? ?? ff ?? ?? ?? ?? ?? 68 40 84 50 00 8d ?? ?? ?? ?? ?? 51 e8 ?? ?? ?? ?? 83 c4 0c}
		$decoder_call = { 55 8b ec 83 c4 f8 33 c0 89 ?? ?? 33 d2 89 ?? ?? 8b ?? ?? 3b ?? ?? 7d ?? 8b ?? ?? 8b ?? ?? 8b ?? ?? 8b ?? ?? 33 ?? ?? ?? ?? ?? ?? 8b ?? ?? 8b ?? ?? 89 ?? ?? 83 ?? ?? ?? 75 ?? 33 d2 89 ?? ?? eb ?? ff ?? ?? ff ?? ?? 8b ?? ?? 3b ?? ?? 7c ?? 59 59 5d c3}

	condition:
		uint16( 0 ) == 0x5a4d and filesize < 2000KB and 2 of them
}

Strings (2 patterns)

IdentifierTypeValueModifiers
$main_callhex{ 68 81 85 50 00 e8 ?? ?? ?? ?? 89 ?? ?? ?? ?? ?? 8d ?? ?? ?? ?? ?? 51 ff ?? ?? ?? ?? ?? e8 ?? ?? ?? ?? 89 ?? ?? ?? ?? ?? ff ?? ?? ?? ?? ?? 68 00 10 00 00 68 b0 …
$decoder_callhex{ 55 8b ec 83 c4 f8 33 c0 89 ?? ?? 33 d2 89 ?? ?? 8b ?? ?? 3b ?? ?? 7d ?? 8b ?? ?? 8b ?? ?? 8b ?? ?? 8b ?? ?? 33 ?? ?? ?? ?? ?? ?? 8b ?? ?? 8b ?? ?? 89 ?? ?? 83 …

Condition

uint16( 0 ) == 0x5a4d and filesize < 2000KB and 2 of them

In plain words (Heuristic)

  • The file must start with “MZ” — a Windows executable (PE).
  • The file must be smaller than 2000KB (a cheap guard that skips large files).
  • At least 2 patterns in the rule must match.

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

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References

Sample hashes

Hashes of samples the author lists in the rule's meta (look them up in your threat-intelligence platform).

  • 829fce14ac8b9ad293076c16a1750502c6b303123c9bd0fb17c1772330577d65

Licence & attribution

Author: @VK_Intel

Source repository: Signature Base (Florian Roth / Nextron) @ 94a1c48d7a

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: 5e030b68-3c29-5203-bb4e-f01850bfbbab

Tags:FILE

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