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MALPEDIA_Win_Zeus_Mailsniffer_Auto

autogenerated rule brought to you by yara-signator

MalwareZeus MailsnifferMalpedia 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: Zeus Mailsniffer.

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

Summary generated from the rule's metadata and condition.

Rule source

win-zeus-mailsniffer-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Zeus_Mailsniffer_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "aaa8e772-89b4-5a81-a4de-d9c0e696d143"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.zeus_mailsniffer"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.zeus_mailsniffer_auto.yar#L1-L128"
		license_url = "N/A"
		logic_hash = "caa1fd0a72d34989de98237506f293f039aa94b0638bba8fb60cbd5148d0d3d9"
		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 = { 6a01 56 e8???????? 83c40c 85c0 7473 807b0e02 }
		$sequence_1 = { 895c2424 897c2428 897c242c ff15???????? 85c0 7562 6a25 }
		$sequence_2 = { 66837ddc00 8b87a0902d01 7403 6a29 58 8d8dd4fdffff 51 }
		$sequence_3 = { 751e 53 8d45f8 50 57 ff750c ff75f4 }
		$sequence_4 = { 742c 56 e8???????? 8b45c0 a3???????? }
		$sequence_5 = { 0f8632050000 8d7910 897ddc 8945d0 8b47f0 }
		$sequence_6 = { 8d44244c 50 8d442454 50 8d44246c 50 }
		$sequence_7 = { 0f83e5020000 6639430e 0f83db020000 0fb703 8bf0 2345e8 c1ee09 }
		$sequence_8 = { f684241c01000020 59 7407 830d????????10 6a5a 8db424ac070000 58 }
		$sequence_9 = { ffd7 85c0 7570 8bc6 50 8d84249c030000 }

	condition:
		7 of them and filesize < 368640
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 6a01 56 e8???????? 83c40c 85c0 7473 807b0e02 }
$sequence_1hex{ 895c2424 897c2428 897c242c ff15???????? 85c0 7562 6a25 }
$sequence_2hex{ 66837ddc00 8b87a0902d01 7403 6a29 58 8d8dd4fdffff 51 }
$sequence_3hex{ 751e 53 8d45f8 50 57 ff750c ff75f4 }
$sequence_4hex{ 742c 56 e8???????? 8b45c0 a3???????? }
$sequence_5hex{ 0f8632050000 8d7910 897ddc 8945d0 8b47f0 }
$sequence_6hex{ 8d44244c 50 8d442454 50 8d44246c 50 }
$sequence_7hex{ 0f83e5020000 6639430e 0f83db020000 0fb703 8bf0 2345e8 c1ee09 }
$sequence_8hex{ f684241c01000020 59 7407 830d????????10 6a5a 8db424ac070000 58 }
$sequence_9hex{ ffd7 85c0 7570 8bc6 50 8d84249c030000 }

Condition

7 of them and filesize < 368640

In plain words (Heuristic)

  • The file must be smaller than 368640 (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.

Open in editor

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: aaa8e772-89b4-5a81-a4de-d9c0e696d143

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