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MALPEDIA_Win_Webmonitor_Auto

autogenerated rule brought to you by yara-signator

MalwareWebmonitorMalpedia 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: Webmonitor.

It defines 16 patterns (0 text, 16 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

win-webmonitor-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Webmonitor_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "3732efb2-6b36-5e6c-94ac-9c96812b2d01"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.webmonitor"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.webmonitor_auto.yar#L1-L166"
		license_url = "N/A"
		logic_hash = "b3dfe96ce488790f0298ba915da8d471590e953d80de53d7b6c6de96cdf61598"
		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 = { 000d???????? 04e4 fd 0468 ff05???????? 000d???????? 04b8 }
		$sequence_1 = { 03c1 99 f7fb 47 }
		$sequence_2 = { ffe1 ba???????? b9???????? ffe1 ba???????? }
		$sequence_3 = { fe04e4 fd 04e0 fd ff01 04e0 fd }
		$sequence_4 = { 04c8 fe04ec fd 04e8 fd ff01 }
		$sequence_5 = { 0f5ac0 50 51 51 f20f110424 e8???????? d91b }
		$sequence_6 = { 0f434520 50 ff75c8 ff15???????? }
		$sequence_7 = { 0f437520 ff15???????? 8d044501000000 50 }
		$sequence_8 = { 0fb6c0 d3e0 8b4de0 03c8 }
		$sequence_9 = { 2bf0 8bc1 99 83e203 03c2 c1f802 2bf8 }
		$sequence_10 = { 3001 a3???????? 30ff 9e 6c 68ff080800 }
		$sequence_11 = { 9e 6c 68ff080800 8a3401 a3???????? 0800 8a30 }
		$sequence_12 = { 38644400 44 8a4100 047e }
		$sequence_13 = { 00e8 17 42 0048a5 }
		$sequence_14 = { 49 81c900ffffff 41 898f04040000 }
		$sequence_15 = { 0f4305???????? 33c9 6800900100 668908 }

	condition:
		7 of them and filesize < 1984512
}

Strings (16 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 000d???????? 04e4 fd 0468 ff05???????? 000d???????? 04b8 }
$sequence_1hex{ 03c1 99 f7fb 47 }
$sequence_2hex{ ffe1 ba???????? b9???????? ffe1 ba???????? }
$sequence_3hex{ fe04e4 fd 04e0 fd ff01 04e0 fd }
$sequence_4hex{ 04c8 fe04ec fd 04e8 fd ff01 }
$sequence_5hex{ 0f5ac0 50 51 51 f20f110424 e8???????? d91b }
$sequence_6hex{ 0f434520 50 ff75c8 ff15???????? }
$sequence_7hex{ 0f437520 ff15???????? 8d044501000000 50 }
$sequence_8hex{ 0fb6c0 d3e0 8b4de0 03c8 }
$sequence_9hex{ 2bf0 8bc1 99 83e203 03c2 c1f802 2bf8 }
$sequence_10hex{ 3001 a3???????? 30ff 9e 6c 68ff080800 }
$sequence_11hex{ 9e 6c 68ff080800 8a3401 a3???????? 0800 8a30 }
$sequence_12hex{ 38644400 44 8a4100 047e }
$sequence_13hex{ 00e8 17 42 0048a5 }
$sequence_14hex{ 49 81c900ffffff 41 898f04040000 }
$sequence_15hex{ 0f4305???????? 33c9 6800900100 668908 }

Condition

7 of them and filesize < 1984512

In plain words (Heuristic)

  • The file must be smaller than 1984512 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

Test this rule in your browser

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Drop a file here or click to chooseScanned locally with YARA-X. Files up to 200 MB.

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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: 3732efb2-6b36-5e6c-94ac-9c96812b2d01

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