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SEKOIA_Hacktool_Win_Cookiekatz

Finds ChromeKatz (CookieKatz version) standalone samples based on the strings

Hack toolSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X
Author
Sekoia.io
Date
2024-10-30
Modified
2024-12-19
Score / Quality
75 / 80

What this rule detects

Finds ChromeKatz (CookieKatz version) standalone samples based on the strings

Targets: Windows PE.

It defines 20 patterns (20 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

hacktool-win-cookiekatz.yarDetection Rule License 1.1
rule SEKOIA_Hacktool_Win_Cookiekatz : FILE
{
	meta:
		description = "Finds ChromeKatz (CookieKatz version) standalone samples based on the strings"
		author = "Sekoia.io"
		id = "a32769bb-4ec4-46c7-9402-21afdf8d4293"
		date = "2024-10-30"
		modified = "2024-12-19"
		reference = "https://github.com/Meckazin/ChromeKatz"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/hacktool_win_cookiekatz.yar#L1-L36"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		hash = "fef9fc33a788489af44b2f732c450d4ef018fbaced7f5471230b282dfd6f1169"
		logic_hash = "a030f551d0f3dedf0f19e22b415aa87dd1c43ab2242db8b5cad14ae6b7695b3a"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$str01 = "CookieKatz.exe" ascii
		$str02 = "--utility-sub-type=network.mojom.NetworkService" wide
		$str03 = "chrome.dll" wide
		$str04 = "msedge.dll" wide
		$str05 = "msedgewebview2.exe" wide
		$str06 = "Failed to read cookie struct" wide
		$str07 = "Failed to read the root node from given address" wide
		$str08 = "Error reading left node" wide
		$str09 = "By Meckazin" ascii
		$str10 = "By default targets first available Chrome process" ascii
		$str11 = "Kittens love cookies too!" ascii
		$str12 = "Attempting to read the cookie value from address: 0x%p" ascii
		$str13 = "szCookieMonster" ascii
		$str14 = "[*] Targeting Chrome" ascii
		$str15 = "[*] Targeting Edge" ascii
		$str16 = "[*] This Cookie map was empty" ascii
		$str17 = "[+] Found browser process: %d" ascii wide
		$str18 = "[*] Targeting process PID: %d" wide
		$str19 = "[*] Found CookieMonster on 0x%p" wide
		$str20 = "[*] CookieMap should be found in address 0x%p" wide

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

Strings (20 patterns)

IdentifierTypeValueModifiers
$str01text"CookieKatz.exe"ascii
$str02text"--utility-sub-type=network.mojom.NetworkService"wide
$str03text"chrome.dll"wide
$str04text"msedge.dll"wide
$str05text"msedgewebview2.exe"wide
$str06text"Failed to read cookie struct"wide
$str07text"Failed to read the root node from given address"wide
$str08text"Error reading left node"wide
$str09text"By Meckazin"ascii
$str10text"By default targets first available Chrome process"ascii
$str11text"Kittens love cookies too!"ascii
$str12text"Attempting to read the cookie value from address: 0x%p"ascii
$str13text"szCookieMonster"ascii
$str14text"[*] Targeting Chrome"ascii
$str15text"[*] Targeting Edge"ascii
$str16text"[*] This Cookie map was empty"ascii
$str17text"[+] Found browser process: %d"ascii wide
$str18text"[*] Targeting process PID: %d"wide
$str19text"[*] Found CookieMonster on 0x%p"wide
$str20text"[*] CookieMap should be found in address 0x%p"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).

  • fef9fc33a788489af44b2f732c450d4ef018fbaced7f5471230b282dfd6f1169

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: a32769bb-4ec4-46c7-9402-21afdf8d4293

Metadata

version1.0
classificationTLP:CLEAR

Tags:FILE