YARA · Malpedia signator rules
MALPEDIA_Win_Micrass_Auto
autogenerated rule brought to you by yara-signator
MalwareMicrassMalpedia 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: Micrass.
It defines 10 patterns (0 text, 10 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
win-micrass-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Micrass_Auto : FILE
{
meta:
= "autogenerated rule brought to you by yara-signator"
= "Felix Bilstein - yara-signator at cocacoding dot com"
= "a229f115-b5ac-5aa3-9ddb-ec5c8630e70f"
= "2026-05-04"
= "2026-05-18"
= "https://malpedia.caad.fkie.fraunhofer.de/details/win.micrass"
= "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.micrass_auto.yar#L1-L118"
= "N/A"
= "639446b0255ff71a4b5f82ebea10985e5191c147bc877240c832d8560fe4064d"
= 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 = { 56 33db 53 6801001f00 ff15???????? 3bc3 }
$sequence_1 = { 770f 0fb7c2 0fbe80e8014100 83e00f eb02 }
$sequence_2 = { c1f905 8d3c8da0dd4000 8bf0 83e61f c1e606 }
$sequence_3 = { 50 8d85c03fffff 50 e8???????? 59 59 85c0 }
$sequence_4 = { a1???????? 33c5 8945fc ff7508 8d85e04fffff 56 }
$sequence_5 = { 56 50 e8???????? 8b85e44fffff 83c40c }
$sequence_6 = { c1f905 8b0c8da0dd4000 83e01f c1e006 f644080401 74cd }
$sequence_7 = { c785fcfefffff4f4f4f4 c78500fffffff4f4f4f4 c78504fffffff4f4f4f4 c78508fffffff4f4f4f4 }
$sequence_8 = { c745a0808084b7 c745a4989b8791 c745a8bc959a90 c745ac9891f4f4 c745b0f4f4f4f4 c745b4f4f4f4f4 }
$sequence_9 = { c745b8f4f4f4f4 c745bcf4f4f4f4 c745c0f4f4f4f4 c745c4f4f4f4f4 }
condition:
7 of them and filesize < 163840
}
Strings (10 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $sequence_0 | hex | { 56 33db 53 6801001f00 ff15???????? 3bc3 } | |
| $sequence_1 | hex | { 770f 0fb7c2 0fbe80e8014100 83e00f eb02 } | |
| $sequence_2 | hex | { c1f905 8d3c8da0dd4000 8bf0 83e61f c1e606 } | |
| $sequence_3 | hex | { 50 8d85c03fffff 50 e8???????? 59 59 85c0 } | |
| $sequence_4 | hex | { a1???????? 33c5 8945fc ff7508 8d85e04fffff 56 } | |
| $sequence_5 | hex | { 56 50 e8???????? 8b85e44fffff 83c40c } | |
| $sequence_6 | hex | { c1f905 8b0c8da0dd4000 83e01f c1e006 f644080401 74cd } | |
| $sequence_7 | hex | { c785fcfefffff4f4f4f4 c78500fffffff4f4f4f4 c78504fffffff4f4f4f4 c78508fffffff4f4f4f4 } | |
| $sequence_8 | hex | { c745a0808084b7 c745a4989b8791 c745a8bc959a90 c745ac9891f4f4 c745b0f4f4f4f4 c745b4f4f4f4f4 } | |
| $sequence_9 | hex | { c745b8f4f4f4f4 c745bcf4f4f4f4 c745c0f4f4f4f4 c745c4f4f4f4f4 } |
Condition
7 of them and filesize < 163840In plain words (Heuristic)
- The file must be smaller than 163840 (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.
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: a229f115-b5ac-5aa3-9ddb-ec5c8630e70f
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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