YARA · Signature Base (Florian Roth / Nextron)

SIGNATURE_BASE_MAL_RANSOM_Gentlemen_Jun26_1

Detects The Gentlemen ransomware Windows locker (Storm-2697), a self-propagating Go-based encryptor

MalwareSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X

Author: Aryu-RU
Date: 2026-06-16
Score / Quality: 80 / 85

What this rule detects

Detects The Gentlemen ransomware Windows locker (Storm-2697), a self-propagating Go-based encryptor

Targets: Windows PE.

It defines 6 patterns (6 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

mal-ransom-gentlemen-jun26-1.yarDetection Rule License 1.1

rule SIGNATURE_BASE_MAL_RANSOM_Gentlemen_Jun26_1 : FILE
{
	meta:
		description = "Detects The Gentlemen ransomware Windows locker (Storm-2697), a self-propagating Go-based encryptor"
		author = "Aryu-RU"
		id = "e93ade6d-c558-426c-b8b5-c6034baf6693"
		date = "2026-06-16"
		modified = "2026-06-16"
		reference = "https://www.microsoft.com/en-us/security/blog/2026/05/28/the-gentlemen-ransomware-dissecting-a-self-propagating-go-encryptor/"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/mal_ransom_gentlemen.yar#L2-L26"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		hash = "22b38dad7da097ea03aa28d0614164cd25fafeb1383dbc15047e34c8050f6f67"
		hash = "f918535f974591ef031bd0f30a8171e3da27a6754e6426a8ba095f83195661c8"
		logic_hash = "0821108fe45c60138cdfb5f79278b7f15c650dad7d94ba8abc559439a49f2c51"
		score = 80
		quality = 85
		tags = "FILE"

	strings:
		$x1 = "README-GENTLEMEN.txt" ascii
		$x2 = "gentlemen.bmp" ascii
		$x3 = "gentlemen_system" ascii
		$s1 = "[+] Encryption started" ascii
		$s2 = "Encrypt only mapped" ascii
		$s3 = "Silent mode" ascii

	condition:
		uint16( 0 ) == 0x5A4D and filesize < 30MB and ( 2 of ( $x* ) or ( 1 of ( $x* ) and 2 of ( $s* ) ) )
}

Strings (6 patterns)

Identifier	Type	Value	Modifiers
$x1	text	"README-GENTLEMEN.txt"	ascii
$x2	text	"gentlemen.bmp"	ascii
$x3	text	"gentlemen_system"	ascii
$s1	text	"[+] Encryption started"	ascii
$s2	text	"Encrypt only mapped"	ascii
$s3	text	"Silent mode"	ascii

Condition

uint16( 0 ) == 0x5A4D and filesize < 30MB and ( 2 of ( $x* ) or ( 1 of ( $x* ) and 2 of ( $s* ) ) )

In plain words (Heuristic)

The file must start with “MZ” — a Windows executable (PE).
The file must be smaller than 30MB (a cheap guard that skips large files).
At least 2 patterns in ( $x* ) must match.
At least 1 patterns in ( $x* ) must match.
At least 2 patterns in ( $s* ) must match.

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References

https://www.microsoft.com/en-us/security/blog/2026/05/28/the-gentlemen-ransomware-dissecting-a-self-propagating-go-encryptor/

Sample hashes

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

22b38dad7da097ea03aa28d0614164cd25fafeb1383dbc15047e34c8050f6f67
f918535f974591ef031bd0f30a8171e3da27a6754e6426a8ba095f83195661c8

Licence & attribution

Author: Aryu-RU

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: e93ade6d-c558-426c-b8b5-c6034baf6693

Tags:FILE