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MALPEDIA_Win_Outlook_Backdoor_Auto

autogenerated rule brought to you by yara-signator

MalwareOutlook BackdoorMalpedia 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: Outlook Backdoor.

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

Summary generated from the rule's metadata and condition.

Rule source

win-outlook-backdoor-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Outlook_Backdoor_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "25cc6be4-aee4-5214-b5d7-8c9f1dc8c5a6"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.outlook_backdoor"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.outlook_backdoor_auto.yar#L1-L132"
		license_url = "N/A"
		logic_hash = "842c87c24f07bbae0fd91c260c830edf0fa4abc10a9d19fdfaac30d66518fcca"
		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 = { 0f8412fdffff ff442410 ff4c2418 837c241800 7fdb e9???????? 56 }
		$sequence_1 = { 6a11 53 ff7004 ff30 53 51 ff5214 }
		$sequence_2 = { 5f 8d45e4 50 56 897de4 e8???????? eb23 }
		$sequence_3 = { 40 83f80c 72f5 8b4d08 8d45ec 50 e8???????? }
		$sequence_4 = { 8bf0 c645fc06 e8???????? 6a00 6a01 8d4dcc 894308 }
		$sequence_5 = { eb3a 8ad0 80ea21 80fa5d 77f0 3c3d }
		$sequence_6 = { 83c618 3bc3 7419 57 8b4808 3b4d08 7509 }
		$sequence_7 = { 8bce e8???????? 8d45c4 50 ff7664 8d45a8 8d4e48 }
		$sequence_8 = { 83ec10 56 57 8d442408 e8???????? 8b30 8b7804 }
		$sequence_9 = { e8???????? 81ec88000000 8365ec00 56 8d856cffffff 50 }

	condition:
		7 of them and filesize < 2912256
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 0f8412fdffff ff442410 ff4c2418 837c241800 7fdb e9???????? 56 }
$sequence_1hex{ 6a11 53 ff7004 ff30 53 51 ff5214 }
$sequence_2hex{ 5f 8d45e4 50 56 897de4 e8???????? eb23 }
$sequence_3hex{ 40 83f80c 72f5 8b4d08 8d45ec 50 e8???????? }
$sequence_4hex{ 8bf0 c645fc06 e8???????? 6a00 6a01 8d4dcc 894308 }
$sequence_5hex{ eb3a 8ad0 80ea21 80fa5d 77f0 3c3d }
$sequence_6hex{ 83c618 3bc3 7419 57 8b4808 3b4d08 7509 }
$sequence_7hex{ 8bce e8???????? 8d45c4 50 ff7664 8d45a8 8d4e48 }
$sequence_8hex{ 83ec10 56 57 8d442408 e8???????? 8b30 8b7804 }
$sequence_9hex{ e8???????? 81ec88000000 8365ec00 56 8d856cffffff 50 }

Condition

7 of them and filesize < 2912256

In plain words (Heuristic)

  • The file must be smaller than 2912256 (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: 25cc6be4-aee4-5214-b5d7-8c9f1dc8c5a6

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