YARA · Malpedia signator rules
MALPEDIA_Win_3Cx_Backdoor_Auto
autogenerated rule brought to you by yara-signator
Malware3Cx BackdoorMalpedia 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: 3Cx Backdoor.
It defines 10 patterns (0 text, 10 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
win-3cx-backdoor-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_3Cx_Backdoor_Auto : FILE
{
meta:
= "autogenerated rule brought to you by yara-signator"
= "Felix Bilstein - yara-signator at cocacoding dot com"
= "1f976734-b5f0-521c-871a-e7babcb44dc6"
= "2026-05-04"
= "2026-05-18"
= "https://malpedia.caad.fkie.fraunhofer.de/details/win.3cx_backdoor"
= "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.3cx_backdoor_auto.yar#L1-L132"
= "N/A"
= "64488f3b81fcdce13d2c1526a75e497414487090bd2d24584ec7c4fe7f730e74"
= 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 = { 747f 4c8d7027 4983e6e0 498946f8 eb0b 488bcb e8???????? }
$sequence_1 = { e8???????? 448bac24d0000000 488bf8 452be5 660f1f440000 e8???????? 33d2 }
$sequence_2 = { e8???????? 4c897de8 4c897df8 4c897d00 0f1000 0f1145e8 0f104810 }
$sequence_3 = { c1e116 4d03c2 33c1 458bd0 4c0fafd7 418d0c10 49c1e820 }
$sequence_4 = { 49894808 48894508 488d4d08 e9???????? 488b78f8 803f02 7534 }
$sequence_5 = { 0f85c7000000 48897c2430 48897c2440 4c89742448 41b804000000 488d1595820300 488d4c2430 }
$sequence_6 = { 4d8d143f 660f1f440000 0fb642f8 4188441208 488b02 4989441210 c642f800 }
$sequence_7 = { c3 488364242000 4c8d05c9b00100 41b9db010000 488d152cb10100 488d0d85b10100 }
$sequence_8 = { 488d1549d6feff 4803ca 813950450000 755f b80b020000 66394118 7554 }
$sequence_9 = { 0f1000 0f11450f 0f104810 0f114d1f 4c897010 48c740180f000000 }
condition:
7 of them and filesize < 585728
}
Strings (10 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $sequence_0 | hex | { 747f 4c8d7027 4983e6e0 498946f8 eb0b 488bcb e8???????? } | |
| $sequence_1 | hex | { e8???????? 448bac24d0000000 488bf8 452be5 660f1f440000 e8???????? 33d2 } | |
| $sequence_2 | hex | { e8???????? 4c897de8 4c897df8 4c897d00 0f1000 0f1145e8 0f104810 } | |
| $sequence_3 | hex | { c1e116 4d03c2 33c1 458bd0 4c0fafd7 418d0c10 49c1e820 } | |
| $sequence_4 | hex | { 49894808 48894508 488d4d08 e9???????? 488b78f8 803f02 7534 } | |
| $sequence_5 | hex | { 0f85c7000000 48897c2430 48897c2440 4c89742448 41b804000000 488d1595820300 488d4c2430 } | |
| $sequence_6 | hex | { 4d8d143f 660f1f440000 0fb642f8 4188441208 488b02 4989441210 c642f800 } | |
| $sequence_7 | hex | { c3 488364242000 4c8d05c9b00100 41b9db010000 488d152cb10100 488d0d85b10100 } | |
| $sequence_8 | hex | { 488d1549d6feff 4803ca 813950450000 755f b80b020000 66394118 7554 } | |
| $sequence_9 | hex | { 0f1000 0f11450f 0f104810 0f114d1f 4c897010 48c740180f000000 } |
Condition
7 of them and filesize < 585728In plain words (Heuristic)
- The file must be smaller than 585728 (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: 1f976734-b5f0-521c-871a-e7babcb44dc6
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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