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SEKOIA_Rat_Win_Xworm_V3

Finds XWorm (version XClient, v3) samples based on characteristic strings

MalwareSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X
Author
Sekoia.io
Date
2023-03-03
Modified
2024-12-19
Score / Quality
75 / 80

What this rule detects

Finds XWorm (version XClient, v3) samples based on characteristic strings

Targets: Windows PE.

It defines 13 patterns (13 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

rat-win-xworm-v3.yarDetection Rule License 1.1
rule SEKOIA_Rat_Win_Xworm_V3 : FILE
{
	meta:
		description = "Finds XWorm (version XClient, v3) samples based on characteristic strings"
		author = "Sekoia.io"
		id = "5fb1cbd3-1e37-43b9-9606-86d896f2150b"
		date = "2023-03-03"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/rat_win_xworm_v3.yar#L1-L30"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		hash = "0016647c3c7031e744c0af6f9eadb73ab5cab1ca4f8ce7633f4aa069b62755cd"
		hash = "07e747a9313732d2dcf7609b6a09ac58d38f5643299440b827ec55f260e33c12"
		hash = "de0127ba872c0677c3594c66b2298edea58d097b5fa697302a16b1689147b147"
		logic_hash = "9a50f41f6c295f48597f6db3f5d9141345b3711ef110a0f925c881f3a75580ca"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$str01 = "$VB$Local_Port" ascii
		$str02 = "$VB$Local_Host" ascii
		$str03 = "get_Jpeg" ascii
		$str04 = "get_ServicePack" ascii
		$str05 = "Select * from AntivirusProduct" wide
		$str06 = "PCRestart" wide
		$str07 = "shutdown.exe /f /r /t 0" wide
		$str08 = "StopReport" wide
		$str09 = "StopDDos" wide
		$str10 = "sendPlugin" wide
		$str11 = "OfflineKeylogger Not Enabled" wide
		$str12 = "-ExecutionPolicy Bypass -File \"" wide
		$str13 = "Content-length: 5235" wide

	condition:
		uint16( 0 ) == 0x5A4D and 8 of them
}

Strings (13 patterns)

IdentifierTypeValueModifiers
$str01text"$VB$Local_Port"ascii
$str02text"$VB$Local_Host"ascii
$str03text"get_Jpeg"ascii
$str04text"get_ServicePack"ascii
$str05text"Select * from AntivirusProduct"wide
$str06text"PCRestart"wide
$str07text"shutdown.exe /f /r /t 0"wide
$str08text"StopReport"wide
$str09text"StopDDos"wide
$str10text"sendPlugin"wide
$str11text"OfflineKeylogger Not Enabled"wide
$str12text"-ExecutionPolicy Bypass -File \""wide
$str13text"Content-length: 5235"wide

Condition

uint16( 0 ) == 0x5A4D and 8 of them

In plain words (Heuristic)

  • The file must start with “MZ” — a Windows executable (PE).
  • At least 8 patterns in the rule must match.

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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).

  • 0016647c3c7031e744c0af6f9eadb73ab5cab1ca4f8ce7633f4aa069b62755cd
  • 07e747a9313732d2dcf7609b6a09ac58d38f5643299440b827ec55f260e33c12
  • de0127ba872c0677c3594c66b2298edea58d097b5fa697302a16b1689147b147

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: 5fb1cbd3-1e37-43b9-9606-86d896f2150b

Metadata

version1.0
classificationTLP:CLEAR

Tags:FILE