YARA · SEKOIA.IO Community

SEKOIA_Killfloor_Avkiller_Strings

Kill-Floor strings

GenericSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X

Author: Sekoia.io
Date: 2024-10-29
Modified: 2024-12-19
Score / Quality: 75 / 80

What this rule detects

Kill-Floor strings

Targets: Windows PE.

It defines 6 patterns (6 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

killfloor-avkiller-strings.yarDetection Rule License 1.1

rule SEKOIA_Killfloor_Avkiller_Strings : FILE
{
	meta:
		description = "Kill-Floor strings"
		author = "Sekoia.io"
		id = "ae6908c3-27d4-4d2c-af21-a9548dfcd487"
		date = "2024-10-29"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/killfloor_avkiller_strings.yar#L1-L25"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		hash = "9f16176ac20f7855fa960d321e156d69"
		hash = "4b019e9ed2de734e242602abce06f7c1"
		hash = "81ae32d9de8fd21acfc61d62f3292277"
		hash = "7cb2c4560e02c25463ec70e222ad0018"
		logic_hash = "e89d0936612104f98b7f56dca09702f31f07868f239c2d11dd738e015e757b3a"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = "sc create aswArPot.sys type=kernel binpath=%s" ascii
		$ = "sc start aswArPot.sys" ascii
		$ = "[*] Enumerating target processes" ascii
		$ = "[*] Entering main loop... " ascii
		$ = "aswArPot.pdb" ascii
		$ = "SeConvertStringSecurityDescriptorToSecurityDescriptor" wide

	condition:
		uint16be( 0 ) == 0x4d5a and filesize < 1MB and filesize > 20KB and 6 of them
}

Strings (6 patterns)

Identifier	Type	Value	Modifiers
$	text	"sc create aswArPot.sys type=kernel binpath=%s"	ascii
$	text	"sc start aswArPot.sys"	ascii
$	text	"[*] Enumerating target processes"	ascii
$	text	"[*] Entering main loop... "	ascii
$	text	"aswArPot.pdb"	ascii
$	text	"SeConvertStringSecurityDescriptorToSecurityDescriptor"	wide

Condition

uint16be( 0 ) == 0x4d5a and filesize < 1MB and filesize > 20KB and 6 of them

In plain words (Heuristic)

The file must start with “MZ” — a Windows executable (PE).
The file must be smaller than 1MB (a cheap guard that skips large files).
The file must be larger than 20KB.
At least 6 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.

Open in editor

References

https://github.com/SEKOIA-IO/Community

Sample hashes

Hashes of samples the author lists in the rule's meta (look them up in your threat-intelligence platform).

9f16176ac20f7855fa960d321e156d69
4b019e9ed2de734e242602abce06f7c1
81ae32d9de8fd21acfc61d62f3292277
7cb2c4560e02c25463ec70e222ad0018

Licence & attribution

Author: Sekoia.io

Source repository: SEKOIA.IO Community @ a438a5901a

Licence: Detection Rule License 1.1 (repository licence)

Original rule

Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.

Rule id: ae6908c3-27d4-4d2c-af21-a9548dfcd487

Metadata

version	1.0
classification	TLP:CLEAR

Tags:FILE

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