YARA · Malpedia signator rules
MALPEDIA_Win_Mewsei_Auto
autogenerated rule brought to you by yara-signator
- 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: Mewsei.
It defines 10 patterns (0 text, 10 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
win-mewsei-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Mewsei_Auto : FILE
{
meta:
= "autogenerated rule brought to you by yara-signator"
= "Felix Bilstein - yara-signator at cocacoding dot com"
= "ff043805-5ac3-54cf-b0e0-78cba5f67524"
= "2026-05-04"
= "2026-05-18"
= "https://malpedia.caad.fkie.fraunhofer.de/details/win.mewsei"
= "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.mewsei_auto.yar#L1-L127"
= "N/A"
= "f355a0c41703f12991cabb20de971b5202bf753a8636b8f2b9f554e6c9d16aac"
= 75
= 75
= "FILE"
= "1"
= "yara-signator v0.6.0"
= "callsandjumps;datarefs;binvalue"
= "20260422"
= "a182e35da64e6d71cb55f125c4d4225196523f14"
= "20260504"
= "CC BY-SA 4.0"
= "TLP:WHITE"
strings:
$sequence_0 = { 6a00 6a01 6a0e 56 ff15???????? 85c0 7411 }
$sequence_1 = { a3???????? a3???????? a1???????? 68???????? 50 c705????????03000000 }
$sequence_2 = { 85c0 750c 6a01 e8???????? 83c404 ebe3 }
$sequence_3 = { 5b c3 6a00 6a00 57 ff15???????? }
$sequence_4 = { f7d2 c1c70a 03fb 0bd7 33d3 0355d4 8b5df8 }
$sequence_5 = { 6a00 8d5117 8bc7 e8???????? b901000000 6a00 6a00 }
$sequence_6 = { 83c418 56 ff15???????? 85c0 7409 56 e8???????? }
$sequence_7 = { 2bf1 8d4900 8a140e 881408 }
$sequence_8 = { 7415 8b04b7 85c0 7409 50 e8???????? }
$sequence_9 = { ff15???????? 85c0 7404 c645fe01 85ff 7409 57 }
condition:
7 of them and filesize < 504832
}
Strings (10 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $sequence_0 | hex | { 6a00 6a01 6a0e 56 ff15???????? 85c0 7411 } | |
| $sequence_1 | hex | { a3???????? a3???????? a1???????? 68???????? 50 c705????????03000000 } | |
| $sequence_2 | hex | { 85c0 750c 6a01 e8???????? 83c404 ebe3 } | |
| $sequence_3 | hex | { 5b c3 6a00 6a00 57 ff15???????? } | |
| $sequence_4 | hex | { f7d2 c1c70a 03fb 0bd7 33d3 0355d4 8b5df8 } | |
| $sequence_5 | hex | { 6a00 8d5117 8bc7 e8???????? b901000000 6a00 6a00 } | |
| $sequence_6 | hex | { 83c418 56 ff15???????? 85c0 7409 56 e8???????? } | |
| $sequence_7 | hex | { 2bf1 8d4900 8a140e 881408 } | |
| $sequence_8 | hex | { 7415 8b04b7 85c0 7409 50 e8???????? } | |
| $sequence_9 | hex | { ff15???????? 85c0 7404 c645fe01 85ff 7409 57 } |
Condition
7 of them and filesize < 504832In plain words (Heuristic)
- The file must be smaller than 504832 (a cheap guard that skips large files).
- At least 7 patterns in the rule must match.
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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)
Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.
Rule id: ff043805-5ac3-54cf-b0e0-78cba5f67524
Metadata
| 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 |
Tags:FILE
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