YARA · Signature Base (Florian Roth / Nextron)

SIGNATURE_BASE_SUSP_APT_MAL_VEILEDSIGNAL_Backdoor_Apr23

Detects marker found in VEILEDSIGNAL backdoor

Suspicious / huntingVeiledsignalSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X

Author: X__Junior
Date: 2023-04-20
Modified: 2023-04-21
Score / Quality: 75 / 85

What this rule detects

Detects marker found in VEILEDSIGNAL backdoor

Associated malware family: Veiledsignal.

It defines 3 patterns (0 text, 3 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

susp-apt-mal-veiledsignal-backdoor-apr23.yarDetection Rule License 1.1

rule SIGNATURE_BASE_SUSP_APT_MAL_VEILEDSIGNAL_Backdoor_Apr23
{
	meta:
		description = "Detects marker found in VEILEDSIGNAL backdoor"
		author = "X__Junior"
		id = "8f0d92b6-d9b0-55e3-b2ca-601d095f5279"
		date = "2023-04-20"
		modified = "2023-04-21"
		reference = "https://www.mandiant.com/resources/blog/3cx-software-supply-chain-compromise"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/apt_nk_tradingtech_apr23.yar#L19-L35"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		hash = "aa318070ad1bf90ed459ac34dc5254acc178baff3202d2ea7f49aaf5a055dd43"
		logic_hash = "ccb482a7634dc24fde03b5730bf28a9e028f8d5a9ad46ba9663d1b520264d8f4"
		score = 75
		quality = 85
		tags = ""

	strings:
		$opb1 = { 81 BD ?? ?? ?? ?? 5E DA F3 76}
		$opb2 = { C7 85 ?? ?? ?? ?? 74 F2 39 DA 66 C7 85 ?? ?? ?? ?? E5 CF}
		$opb3 = { C7 85 ?? ?? ?? ?? 74 F2 39 DA B9 00 04 00 00 66 C7 85 ?? ?? ?? ?? E5 CF }

	condition:
		2 of them
}

Strings (3 patterns)

Identifier	Type	Value
$opb1	hex	{ 81 BD ?? ?? ?? ?? 5E DA F3 76}
$opb2	hex	{ C7 85 ?? ?? ?? ?? 74 F2 39 DA 66 C7 85 ?? ?? ?? ?? E5 CF}
$opb3	hex	{ C7 85 ?? ?? ?? ?? 74 F2 39 DA B9 00 04 00 00 66 C7 85 ?? ?? ?? ?? E5 CF }

Condition

2 of them

In plain words (Heuristic)

At least 2 patterns in the rule must match.

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References

https://www.mandiant.com/resources/blog/3cx-software-supply-chain-compromise

Sample hashes

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

aa318070ad1bf90ed459ac34dc5254acc178baff3202d2ea7f49aaf5a055dd43

Licence & attribution

Author: X__Junior

Source repository: Signature Base (Florian Roth / Nextron) @ 94a1c48d7a

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: 8f0d92b6-d9b0-55e3-b2ca-601d095f5279

SIGNATURE_BASE_APT_MAL_VEILEDSIGNAL_Backdoor_Apr23
APT / threat actorSignature Base (Florian Roth / Nextron)· X__Junior· 2023-04-20
SIGNATURE_BASE_APT_MAL_VEILEDSIGNAL_Backdoor_Apr23_2
APT / threat actorSignature Base (Florian Roth / Nextron)· X__Junior· 2023-04-29
SIGNATURE_BASE_APT_MAL_VEILEDSIGNAL_Backdoor_Apr23_3
APT / threat actorSignature Base (Florian Roth / Nextron)· X__Junior· 2023-04-29
SIGNATURE_BASE_APT_MAL_VEILEDSIGNAL_Backdoor_Apr23_4
APT / threat actorSignature Base (Florian Roth / Nextron)· X__Junior· 2023-04-29
SIGNATURE_BASE_APT_NK_MAL_M_Hunting_VEILEDSIGNAL_1
APT / threat actorSignature Base (Florian Roth / Nextron)· Mandiant· 2023-04-20
SIGNATURE_BASE_APT_NK_MAL_M_Hunting_VEILEDSIGNAL_2
APT / threat actorSignature Base (Florian Roth / Nextron)· Mandiant· 2023-04-20
SIGNATURE_BASE_APT_NK_MAL_M_Hunting_VEILEDSIGNAL_3
APT / threat actorSignature Base (Florian Roth / Nextron)· Mandiant· 2023-04-20
SIGNATURE_BASE_APT_NK_MAL_M_Hunting_VEILEDSIGNAL_4
APT / threat actorSignature Base (Florian Roth / Nextron)· Mandiant· 2023-04-20

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