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DITEKSHEN_MALWARE_Win_Polar

Detects Polar ransomware

MalwarePolarditekSHen detectionBSD 2-Clause LicenseCompiles with YARA-X
Author
ditekSHen
Date
2020-11-06
Modified
2024-11-01
Score / Quality
75 / 75

What this rule detects

Detects Polar ransomware

Associated malware family: Polar.

Targets: Windows PE.

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

Summary generated from the rule's metadata and condition.

Rule source

malware-win-polar.yarBSD 2-Clause License
rule DITEKSHEN_MALWARE_Win_Polar : FILE
{
	meta:
		description = "Detects Polar ransomware"
		author = "ditekSHen"
		id = "ab4e4478-5417-5918-b5df-5b6ffe7438a9"
		date = "2020-11-06"
		modified = "2024-11-01"
		reference = "https://github.com/ditekshen/detection"
		source_url = "https://github.com/ditekshen/detection/blob/e76c93dcdedff04076380ffc60ea54e45b313635/yara/malware.yar#L2102-L2123"
		license_url = "https://github.com/ditekshen/detection/blob/e76c93dcdedff04076380ffc60ea54e45b313635/LICENSE.txt"
		logic_hash = "4f05a8ace9a03d02f54f0ebdd5349d1d1b23db8e34aa71edd44eebf02b88745c"
		score = 75
		quality = 75
		tags = "FILE"
		clamav_sig = "MALWARE.Win.Ransomware.Polar"

	strings:
		$s1 = "Encrypt Failed ! ErrorMessage :" wide
		$s2 = ".locked" fullword wide
		$s3 = ".cryptd" fullword wide
		$s4 = "$SysReset" fullword wide
		$s5 = "Polar.Properties.Resources" ascii wide
		$s6 = "AES_EnDecryptor.Basement" fullword ascii
		$s7 = "RunCMDCommand" fullword ascii
		$s8 = "killerps_list" fullword ascii
		$s9 = "clearlog" fullword ascii
		$s10 = "encryptFile" fullword ascii
		$s11 = "changeBackPictrue" fullword ascii
		$pdb1 = "\\Ransomware_ALL_encode\\dir_file\\obj\\x86\\Release\\Encode.pdb" ascii
		$pdb2 = "\\Ransomware_ALL_encode\\dir_file\\obj\\x64\\Release\\Encode.pdb" ascii

	condition:
		uint16( 0 ) == 0x5a4d and ( 8 of ( $s* ) or ( 1 of ( $pdb* ) and 2 of ( $s* ) ) )
}

Strings (13 patterns)

IdentifierTypeValueModifiers
$s1text"Encrypt Failed ! ErrorMessage :"wide
$s2text".locked"fullword wide
$s3text".cryptd"fullword wide
$s4text"$SysReset"fullword wide
$s5text"Polar.Properties.Resources"ascii wide
$s6text"AES_EnDecryptor.Basement"fullword ascii
$s7text"RunCMDCommand"fullword ascii
$s8text"killerps_list"fullword ascii
$s9text"clearlog"fullword ascii
$s10text"encryptFile"fullword ascii
$s11text"changeBackPictrue"fullword ascii
$pdb1text"\\Ransomware_ALL_encode\\dir_file\\obj\\x86\\Release\\Encode.pdb"ascii
$pdb2text"\\Ransomware_ALL_encode\\dir_file\\obj\\x64\\Release\\Encode.pdb"ascii

Condition

uint16( 0 ) == 0x5a4d and ( 8 of ( $s* ) or ( 1 of ( $pdb* ) and 2 of ( $s* ) ) )

In plain words (Heuristic)

  • The file must start with “MZ” — a Windows executable (PE).
  • At least 8 patterns in ( $s* ) must match.
  • At least 1 patterns in ( $pdb* ) must match.
  • At least 2 patterns in ( $s* ) must match.

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References

Licence & attribution

Author: ditekSHen

Source repository: ditekSHen detection @ e76c93dcde

Licence: BSD 2-Clause License (repository licence)

Copyright notice: Copyright 2021 by ditekSHen (https://github.com/ditekshen/detection).

Original rule

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

Rule id: ab4e4478-5417-5918-b5df-5b6ffe7438a9

Metadata

clamav_sigMALWARE.Win.Ransomware.Polar

Tags:FILE