YARA · SEKOIA.IO Community
SEKOIA_Apt_Apt41_Keyplug_Dropper
Detects a dropper used by keyplug
- Author
- Sekoia.io
- Date
- 2024-06-12
- Modified
- 2024-12-19
- Score / Quality
- 75 / 80
What this rule detects
Detects a dropper used by keyplug
Targets: Windows PE.
It defines 4 patterns (4 text, 0 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
apt-apt41-keyplug-dropper.yarDetection Rule License 1.1
rule SEKOIA_Apt_Apt41_Keyplug_Dropper : FILE
{
meta:
= "Detects a dropper used by keyplug"
= "Sekoia.io"
= "b6740371-c4c3-437e-8235-0bd4f7b9c3f5"
= "2024-06-12"
= "2024-12-19"
= "https://github.com/SEKOIA-IO/Community"
= "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/apt_apt41_keyplug_dropper.yar#L1-L20"
= "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
= "a61f57302d8fe58ed8b77542c94159acbc36a3bd52c204171e76e668d10a74e7"
= 75
= 80
= "FILE"
= "1.0"
= "TLP:CLEAR"
strings:
$ = "C:\\ProgramData\\pfm.ico" wide
$ = "C:\\\\ProgramData\\\\pfm.ico" wide
$ = "67f8de349abc5ghi" wide
$ = "3abc64597f8diegh" wide
condition:
uint16be( 0 ) == 0x4d5a and filesize < 2MB and any of them
}
Strings (4 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $ | text | "C:\\ProgramData\\pfm.ico" | wide |
| $ | text | "C:\\\\ProgramData\\\\pfm.ico" | wide |
| $ | text | "67f8de349abc5ghi" | wide |
| $ | text | "3abc64597f8diegh" | wide |
Condition
uint16be( 0 ) == 0x4d5a and filesize < 2MB and any of themIn plain words (Heuristic)
- The file must start with “MZ” — a Windows executable (PE).
- The file must be smaller than 2MB (a cheap guard that skips large files).
- At least one pattern in the rule must match.
Test this rule in your browser
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References
Licence & attribution
Author: Sekoia.io
Source repository: SEKOIA.IO Community @ a438a5901a
Licence: Detection Rule License 1.1 (repository licence)
Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.
Rule id: b6740371-c4c3-437e-8235-0bd4f7b9c3f5
Metadata
| version | 1.0 |
|---|---|
| classification | TLP:CLEAR |
Tags:FILE
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