YARA · Malpedia signator rules
MALPEDIA_Win_Bottomloader_Auto
autogenerated rule brought to you by yara-signator
MalwareBottomloaderMalpedia 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: Bottomloader.
It defines 10 patterns (0 text, 10 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
win-bottomloader-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Bottomloader_Auto : FILE
{
meta:
= "autogenerated rule brought to you by yara-signator"
= "Felix Bilstein - yara-signator at cocacoding dot com"
= "46f34a43-3db5-5ef1-9958-b6c9596ba25b"
= "2026-05-04"
= "2026-05-18"
= "https://malpedia.caad.fkie.fraunhofer.de/details/win.bottomloader"
= "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.bottomloader_auto.yar#L1-L132"
= "N/A"
= "b0d59c0f9fc58fd278ab5fcc06a80a7243ece9019c1e96be659c478b7b007c4d"
= 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 = { 488b5708 488b07 48898500ffffff 48899508ffffff 4c8d8d00ffffff 448b4520 498b542408 }
$sequence_1 = { 4c8b8d58fcffff 450fbe2431 488d0d6e3b0800 4883ec20 e8???????? 4883c420 4989c6 }
$sequence_2 = { 4883ec30 498bf9 8b0a e8???????? 90 488d1dfa5b0400 488d35bb140200 }
$sequence_3 = { 488b02 488b5208 488945e0 488955e8 4c8d4de0 4c8b4520 488d0d06500a00 }
$sequence_4 = { 4989f8 ba47050000 488d0de8710800 e8???????? 488bc6 482bc7 488945f0 }
$sequence_5 = { 488d056a1e0400 488945d8 48c745d00f000000 488d55d0 b903000000 }
$sequence_6 = { 488985f0feffff 488995f8feffff 488d8df0feffff 488b9570feffff 4883ec20 e8???????? 4883c420 }
$sequence_7 = { 654c8b142558000000 4f8b24ca bac00a0000 498b3c14 4c8b8788000000 4983c008 4c8945e0 }
$sequence_8 = { 4531c9 4d89c8 ba9f090000 488d0d4a190b00 e8???????? 4c8b9508ffffff 410fb632 }
$sequence_9 = { 48894590 41b901000000 4531c0 bafe060000 488d0d10e80500 e8???????? 488b5e08 }
condition:
7 of them and filesize < 1955840
}
Strings (10 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $sequence_0 | hex | { 488b5708 488b07 48898500ffffff 48899508ffffff 4c8d8d00ffffff 448b4520 498b542408 } | |
| $sequence_1 | hex | { 4c8b8d58fcffff 450fbe2431 488d0d6e3b0800 4883ec20 e8???????? 4883c420 4989c6 } | |
| $sequence_2 | hex | { 4883ec30 498bf9 8b0a e8???????? 90 488d1dfa5b0400 488d35bb140200 } | |
| $sequence_3 | hex | { 488b02 488b5208 488945e0 488955e8 4c8d4de0 4c8b4520 488d0d06500a00 } | |
| $sequence_4 | hex | { 4989f8 ba47050000 488d0de8710800 e8???????? 488bc6 482bc7 488945f0 } | |
| $sequence_5 | hex | { 488d056a1e0400 488945d8 48c745d00f000000 488d55d0 b903000000 } | |
| $sequence_6 | hex | { 488985f0feffff 488995f8feffff 488d8df0feffff 488b9570feffff 4883ec20 e8???????? 4883c420 } | |
| $sequence_7 | hex | { 654c8b142558000000 4f8b24ca bac00a0000 498b3c14 4c8b8788000000 4983c008 4c8945e0 } | |
| $sequence_8 | hex | { 4531c9 4d89c8 ba9f090000 488d0d4a190b00 e8???????? 4c8b9508ffffff 410fb632 } | |
| $sequence_9 | hex | { 48894590 41b901000000 4531c0 bafe060000 488d0d10e80500 e8???????? 488b5e08 } |
Condition
7 of them and filesize < 1955840In plain words (Heuristic)
- The file must be smaller than 1955840 (a cheap guard that skips large files).
- At least 7 patterns in the rule must match.
Test this rule in your browser
Drop a file to scan it with this rule using YARA-X compiled to WebAssembly. Nothing is uploaded.
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: 46f34a43-3db5-5ef1-9958-b6c9596ba25b
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
Related rules
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04