YARA · ESET malware-ioc

ESET_Apt_Windows_TA410_Flowcloud_Fcclient_Strings

Strings found in fcClient/rescure.dat module.

APT / threat actorESET malware-iocBSD 2-Clause LicenseCompiles with YARA-X

Author: ESET Research
Date: 2021-10-12
Modified: 2022-04-27
Score / Quality: 75 / 80

What this rule detects

Strings found in fcClient/rescure.dat module.

Targets: Windows PE.

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

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

apt-windows-ta410-flowcloud-fcclient-strings.yarBSD 2-Clause License

rule ESET_Apt_Windows_TA410_Flowcloud_Fcclient_Strings : FILE
{
	meta:
		description = "Strings found in fcClient/rescure.dat module."
		author = "ESET Research"
		id = "876bae0b-2612-559b-9ead-b633a3789663"
		date = "2021-10-12"
		modified = "2022-04-27"
		reference = "https://github.com/eset/malware-ioc/"
		source_url = "https://github.com/eset/malware-ioc/blob/17baf44964a77368e9149f4f593eb098beddf1c5/ta410/ta410.yar#L617-L639"
		license_url = "https://github.com/eset/malware-ioc/blob/17baf44964a77368e9149f4f593eb098beddf1c5/LICENSE"
		logic_hash = "c05b7031a5aec1bcf29eca06c010c402edeb24a093a2043dbc21781dff22c7fe"
		score = 75
		quality = 80
		tags = "FILE"
		license = "BSD 2-Clause"
		version = "1"

	strings:
		$s1 = "df257bdd-847c-490e-9ef9-1d7dc883d3c0"
		$s2 = "\\{2AFF264E-B722-4359-8E0F-947B85594A9A}"
		$s3 = "Global\\{26C96B51-2B5D-4D7B-BED1-3DCA4848EDD1}" wide
		$s4 = "{804423C2-F490-4ac3-BFA5-13DEDE63A71A}" wide
		$s5 = "{A5124AF5-DF23-49bf-B0ED-A18ED3DEA027}" wide
		$s6 = "XXXModule_func.dll"
		$driver1 = "\\drivers\\hidmouse.sys" wide fullword
		$driver2 = "\\drivers\\hidusb.sys" wide fullword

	condition:
		uint16( 0 ) == 0x5a4d and ( any of ( $s* ) or all of ( $driver* ) )
}

Strings (8 patterns)

Identifier	Type	Value	Modifiers
$s1	text	"df257bdd-847c-490e-9ef9-1d7dc883d3c0"
$s2	text	"\\{2AFF264E-B722-4359-8E0F-947B85594A9A}"
$s3	text	"Global\\{26C96B51-2B5D-4D7B-BED1-3DCA4848EDD1}"	wide
$s4	text	"{804423C2-F490-4ac3-BFA5-13DEDE63A71A}"	wide
$s5	text	"{A5124AF5-DF23-49bf-B0ED-A18ED3DEA027}"	wide
$s6	text	"XXXModule_func.dll"
$driver1	text	"\\drivers\\hidmouse.sys"	wide fullword
$driver2	text	"\\drivers\\hidusb.sys"	wide fullword

Condition

uint16( 0 ) == 0x5a4d and ( any of ( $s* ) or all of ( $driver* ) )

In plain words (Heuristic)

The file must start with “MZ” — a Windows executable (PE).
All patterns in ( $driver* ) must match.
At least one pattern in ( $s* ) 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

https://github.com/eset/malware-ioc/

Licence & attribution

Author: ESET Research

Source repository: ESET malware-ioc @ 17baf44964

Licence: BSD 2-Clause License (stated in the rule's own meta)

“BSD 2-Clause”

Original rule

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

Rule id: 876bae0b-2612-559b-9ead-b633a3789663

Metadata

version	1

Tags:FILE

ESET_Apt_Windows_Invisimole
APT / threat actorESET malware-ioc· ESET Research· 2021-05-17
ESET_Apt_Windows_Invisimole_CPL_Loader
APT / threat actorESET malware-ioc· ESET Research· 2021-05-17
ESET_Apt_Windows_Invisimole_DNS_Downloader
APT / threat actorESET malware-ioc· ESET Research· 2021-05-17
ESET_Apt_Windows_Invisimole_Logs
APT / threat actorESET malware-ioc· ESET Research· 2021-05-17
ESET_Apt_Windows_Invisimole_SFX_Dropper
APT / threat actorESET malware-ioc· ESET Research· 2021-05-17
ESET_Apt_Windows_TA410_Lookback_Decryption
APT / threat actorESET malware-ioc· ESET Research· 2021-10-12
ESET_Apt_Windows_TA410_Lookback_HTTP
APT / threat actorESET malware-ioc· ESET Research· 2021-10-12
ESET_Apt_Windows_TA410_Lookback_Loader
APT / threat actorESET malware-ioc· ESET Research· 2021-10-12