YARA · Malpedia signator rules
MALPEDIA_Win_Casper_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: Casper.
It defines 10 patterns (0 text, 10 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
win-casper-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Casper_Auto : FILE
{
meta:
= "autogenerated rule brought to you by yara-signator"
= "Felix Bilstein - yara-signator at cocacoding dot com"
= "483c8201-f37a-53e7-9113-9d548aa8d32e"
= "2026-05-04"
= "2026-05-18"
= "https://malpedia.caad.fkie.fraunhofer.de/details/win.casper"
= "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.casper_auto.yar#L1-L131"
= "N/A"
= "89ad7b43d1f5ceb79d3ec58d7e3b639bca64e16a9f104c9726dbf8ed7bb127dc"
= 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 = { 3bc7 0f8445010000 68???????? e8???????? 3bc7 0f8433010000 be???????? }
$sequence_1 = { c745f800020000 50 68???????? e8???????? 59 8b4d08 50 }
$sequence_2 = { 894770 85c0 742d 680af1d476 56 53 e8???????? }
$sequence_3 = { 50 e8???????? 85c0 7428 ff75fc 57 e8???????? }
$sequence_4 = { 8945f8 85c0 742f 8d771c e8???????? }
$sequence_5 = { 727d 8b01 ba4d5a0000 663910 7571 8b503c }
$sequence_6 = { ff7508 56 e8???????? 85c0 756e 50 8d45fc }
$sequence_7 = { 83c40c 56 8d85fcefffff 6a00 50 e8???????? 83c40c }
$sequence_8 = { 59 8bc7 5f 5e c20400 8b06 85c0 }
$sequence_9 = { 895df8 894df4 83c010 c745f006000000 eb03 8b5df8 8bf7 }
condition:
7 of them and filesize < 434176
}
Strings (10 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $sequence_0 | hex | { 3bc7 0f8445010000 68???????? e8???????? 3bc7 0f8433010000 be???????? } | |
| $sequence_1 | hex | { c745f800020000 50 68???????? e8???????? 59 8b4d08 50 } | |
| $sequence_2 | hex | { 894770 85c0 742d 680af1d476 56 53 e8???????? } | |
| $sequence_3 | hex | { 50 e8???????? 85c0 7428 ff75fc 57 e8???????? } | |
| $sequence_4 | hex | { 8945f8 85c0 742f 8d771c e8???????? } | |
| $sequence_5 | hex | { 727d 8b01 ba4d5a0000 663910 7571 8b503c } | |
| $sequence_6 | hex | { ff7508 56 e8???????? 85c0 756e 50 8d45fc } | |
| $sequence_7 | hex | { 83c40c 56 8d85fcefffff 6a00 50 e8???????? 83c40c } | |
| $sequence_8 | hex | { 59 8bc7 5f 5e c20400 8b06 85c0 } | |
| $sequence_9 | hex | { 895df8 894df4 83c010 c745f006000000 eb03 8b5df8 8bf7 } |
Condition
7 of them and filesize < 434176In plain words (Heuristic)
- The file must be smaller than 434176 (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: 483c8201-f37a-53e7-9113-9d548aa8d32e
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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