YARA · Malpedia signator rules
MALPEDIA_Win_Bolek_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: Bolek.
It defines 10 patterns (0 text, 10 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
win-bolek-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Bolek_Auto : FILE
{
meta:
= "autogenerated rule brought to you by yara-signator"
= "Felix Bilstein - yara-signator at cocacoding dot com"
= "e0711f3d-dc08-5700-b33c-1b4157838473"
= "2026-05-04"
= "2026-05-18"
= "https://malpedia.caad.fkie.fraunhofer.de/details/win.bolek"
= "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.bolek_auto.yar#L1-L134"
= "N/A"
= "7f48551f5c704655f1f9b7e798e400d056ae3ccf224a062456c04b2346e75270"
= 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 = { 8af3 66895df8 8bc3 bf00010000 8801 40 41 }
$sequence_1 = { 894c2410 3c3c 7529 68???????? b8f4010000 2bc7 68???????? }
$sequence_2 = { e8???????? 8bd8 59 59 85db 7e40 ba???????? }
$sequence_3 = { ff15???????? 85c0 740b 8b8c24d4000000 8bd6 eb11 0f57c0 }
$sequence_4 = { 8d7df2 ab 6a02 59 6a06 ab 6a01 }
$sequence_5 = { ff15???????? 83c40c 837dd000 741c 8d8584fdffff 50 8d458c }
$sequence_6 = { ff7508 e8???????? ebbf ff750c ff7508 e8???????? ebb2 }
$sequence_7 = { ff7610 896c242c 894c2428 e8???????? 83c418 85c0 0f8882000000 }
$sequence_8 = { c685d8feffffc3 8d95d8feffff c685f8feffff01 8bce e8???????? 5e 8be5 }
$sequence_9 = { 8bf8 83c40c 85ff 0f888a000000 8b44240c 39442420 757c }
condition:
7 of them and filesize < 892928
}
Strings (10 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $sequence_0 | hex | { 8af3 66895df8 8bc3 bf00010000 8801 40 41 } | |
| $sequence_1 | hex | { 894c2410 3c3c 7529 68???????? b8f4010000 2bc7 68???????? } | |
| $sequence_2 | hex | { e8???????? 8bd8 59 59 85db 7e40 ba???????? } | |
| $sequence_3 | hex | { ff15???????? 85c0 740b 8b8c24d4000000 8bd6 eb11 0f57c0 } | |
| $sequence_4 | hex | { 8d7df2 ab 6a02 59 6a06 ab 6a01 } | |
| $sequence_5 | hex | { ff15???????? 83c40c 837dd000 741c 8d8584fdffff 50 8d458c } | |
| $sequence_6 | hex | { ff7508 e8???????? ebbf ff750c ff7508 e8???????? ebb2 } | |
| $sequence_7 | hex | { ff7610 896c242c 894c2428 e8???????? 83c418 85c0 0f8882000000 } | |
| $sequence_8 | hex | { c685d8feffffc3 8d95d8feffff c685f8feffff01 8bce e8???????? 5e 8be5 } | |
| $sequence_9 | hex | { 8bf8 83c40c 85ff 0f888a000000 8b44240c 39442420 757c } |
Condition
7 of them and filesize < 892928In plain words (Heuristic)
- The file must be smaller than 892928 (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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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: e0711f3d-dc08-5700-b33c-1b4157838473
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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