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MALPEDIA_Win_Fatal_Rat_Auto

autogenerated rule brought to you by yara-signator

MalwareFatal RatMalpedia signator rulesCreative Commons Attribution-ShareAlike 4.0Compiles with YARA-X
Author
Felix Bilstein - yara-signator at cocacoding dot com
Date
2026-05-04
Modified
2026-05-18
Score / Quality
75 / 75

What this rule detects

autogenerated rule brought to you by yara-signator

Associated malware family: Fatal Rat.

It defines 10 patterns (0 text, 10 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

win-fatal-rat-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Fatal_Rat_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "ec19e1f9-e8cd-5f88-872b-ba05d62d5b04"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.fatal_rat"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.fatal_rat_auto.yar#L1-L131"
		license_url = "N/A"
		logic_hash = "24febda351895f7660661e4345fe2bbb902ae75dcd74ecdb9a8cb74f1cd5fd28"
		score = 75
		quality = 75
		tags = "FILE"
		version = "1"
		tool = "yara-signator v0.6.0"
		signator_config = "callsandjumps;datarefs;binvalue"
		malpedia_rule_date = "20260422"
		malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
		malpedia_version = "20260504"
		malpedia_license = "CC BY-SA 4.0"
		malpedia_sharing = "TLP:WHITE"

	strings:
		$sequence_0 = { ff15???????? 50 ffd6 85c0 7503 2145fc }
		$sequence_1 = { 8d45e0 50 c645e26c c645e36d c645e46f c645e56e }
		$sequence_2 = { 7405 83c8ff eb02 8bc3 5f 5e 5b }
		$sequence_3 = { 50 ff15???????? 8bf0 3bf3 8975f8 0f840b010000 33ff }
		$sequence_4 = { e8???????? 56 e8???????? ffb630af0100 8b8e40af0100 8b5510 894508 }
		$sequence_5 = { 803900 75fa 56 57 8b7d10 8bd7 }
		$sequence_6 = { ff75ec ffd6 53 6a01 57 ff75ec ffd6 }
		$sequence_7 = { 833901 7407 b800000800 eb0c 8b4904 50 ff750c }
		$sequence_8 = { 6685c0 741f 83ffff 7e1a 83fe40 7e15 83fe5d }
		$sequence_9 = { 0f86ec000000 8365f000 8945ec df6dec dc0d???????? dc05???????? e8???????? }

	condition:
		7 of them and filesize < 344064
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ ff15???????? 50 ffd6 85c0 7503 2145fc }
$sequence_1hex{ 8d45e0 50 c645e26c c645e36d c645e46f c645e56e }
$sequence_2hex{ 7405 83c8ff eb02 8bc3 5f 5e 5b }
$sequence_3hex{ 50 ff15???????? 8bf0 3bf3 8975f8 0f840b010000 33ff }
$sequence_4hex{ e8???????? 56 e8???????? ffb630af0100 8b8e40af0100 8b5510 894508 }
$sequence_5hex{ 803900 75fa 56 57 8b7d10 8bd7 }
$sequence_6hex{ ff75ec ffd6 53 6a01 57 ff75ec ffd6 }
$sequence_7hex{ 833901 7407 b800000800 eb0c 8b4904 50 ff750c }
$sequence_8hex{ 6685c0 741f 83ffff 7e1a 83fe40 7e15 83fe5d }
$sequence_9hex{ 0f86ec000000 8365f000 8945ec df6dec dc0d???????? dc05???????? e8???????? }

Condition

7 of them and filesize < 344064

In plain words (Heuristic)

  • The file must be smaller than 344064 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

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References

Licence & attribution

Author: Felix Bilstein - yara-signator at cocacoding dot com

Source repository: Malpedia signator rules @ c901f97b7d

Licence: Creative Commons Attribution-ShareAlike 4.0 (repository licence)

Original rule

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

Rule id: ec19e1f9-e8cd-5f88-872b-ba05d62d5b04

Metadata

version1
toolyara-signator v0.6.0
signator_configcallsandjumps;datarefs;binvalue
malpedia_rule_date20260422
malpedia_hasha182e35da64e6d71cb55f125c4d4225196523f14
malpedia_version20260504
malpedia_licenseCC BY-SA 4.0
malpedia_sharingTLP:WHITE

Tags:FILE