Skip to content

YARA · SEKOIA.IO Community

SEKOIA_Spyware_And_Fastfire

Detect the FastFire malware

MalwareSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X
Author
Sekoia.io
Date
2022-11-03
Modified
2024-12-19
Score / Quality
75 / 80

What this rule detects

Detect the FastFire malware

It defines 8 patterns (6 text, 2 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

spyware-and-fastfire.yarDetection Rule License 1.1
rule SEKOIA_Spyware_And_Fastfire : FILE
{
	meta:
		description = "Detect the FastFire malware"
		author = "Sekoia.io"
		id = "93c0ffd5-faa5-4ead-8848-1c44b459dc29"
		date = "2022-11-03"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/spyware_and_fastfire.yar#L1-L23"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		logic_hash = "2600fc0a8fc6279936decf80256be1fc8cb581a59ef6646fe48b5885e104365e"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$funct1 = {22 00 87 18 70 20 f3 ae 40 00 6e 10 f4 ae 00 00 0c 04 1f 04 16 19 13 00 28 23 6e 20 e3 ae 04 00 12 10 6e 20 e5 ae 04 00 1a 00 25 19 6e 20 ea ae 04 00 28 05 0d 00 6e 10 ef ae 00 00 6e 10 da ae 04 00 6e 10 e1 ae 04 00 0a 00 13 01 c8 00 32 10 20 00 1c 00 ea 17 6e 10 73 ad 00 00 0c 00 22 01 60 18 70 10 5d ae 01 00 1a 02 ff 50 6e 20 69 ae 21 00 6e 10 e1 ae 04 00 0a 04 6e 20 64 ae 41 00 6e 10 72 ae 01 00 0c 04 71 20 1d 09 40 00}
		$funct2 = {22 00 77 00 1a 01 88 56 70 20 f1 02 10 00 15 01 00 10 6e 20 f4 02 10 00 1a 01 80 8d 6e 20 32 ae 13 00 0a 01 38 01 0b 00 1a 01 25 76 71 10 b3 06 01 00 0c 01 6e 20 22 03 10 00 1a 01 56 61 6e 20 32 ae 13 00 0a 01 38 01 0b 00 1a 01 23 76 71 10 b3 06 01 00 0c 01 6e 20 22 03 10 00 1a 01 55 66 6e 20 32 ae 13 00 0a 03 38 03 0b 00 1a 03 24 76 71 10 b3 06 03 00 0c 03 6e 20 22 03 30 00 13 03 64 00 15 01 00 08 71 40 07 02 32 10 0c 03 11 03}
		$s0 = "TokenResult{token="
		$s1 = "[-] Send Resp Code ="
		$s2 = "/report_token/report_token.php?token="
		$s3 = "naver"
		$s4 = "daum"
		$s5 = "facebook"

	condition:
		uint32be( 0 ) == 0x6465780A and ( 1 of ( $funct* ) or all of ( $s* ) )
}

Strings (8 patterns)

IdentifierTypeValueModifiers
$funct1hex{22 00 87 18 70 20 f3 ae 40 00 6e 10 f4 ae 00 00 0c 04 1f 04 16 19 13 00 28 23 6e 20 e3 ae 04 00 12 10 6e 20 e5 ae 04 00 1a 00 25 19 6e 20 ea ae 04 00 28 05 0d …
$funct2hex{22 00 77 00 1a 01 88 56 70 20 f1 02 10 00 15 01 00 10 6e 20 f4 02 10 00 1a 01 80 8d 6e 20 32 ae 13 00 0a 01 38 01 0b 00 1a 01 25 76 71 10 b3 06 01 00 0c 01 6e …
$s0text"TokenResult{token="
$s1text"[-] Send Resp Code ="
$s2text"/report_token/report_token.php?token="
$s3text"naver"
$s4text"daum"
$s5text"facebook"

Condition

uint32be( 0 ) == 0x6465780A and ( 1 of ( $funct* ) or all of ( $s* ) )

In plain words (Heuristic)

  • All patterns in ( $s* ) must match.
  • At least 1 patterns in ( $funct* ) 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.

Open in editor

References

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: 93c0ffd5-faa5-4ead-8848-1c44b459dc29

Metadata

version1.0
classificationTLP:CLEAR

Tags:FILE