YARA · ESET malware-ioc

ESET_Apt_Windows_TA410_Lookback_HTTP

Matches LookBack's hardcoded HTTP request

APT / threat actorLookbackESET 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

Matches LookBack's hardcoded HTTP request

Associated malware family: Lookback.

Targets: Windows PE.

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

Summary generated from the rule's metadata and condition.

Rule source

Download .yar

apt-windows-ta410-lookback-http.yarBSD 2-Clause License

rule ESET_Apt_Windows_TA410_Lookback_HTTP : FILE
{
	meta:
		description = "Matches LookBack's hardcoded HTTP request"
		author = "ESET Research"
		id = "ca4ee437-5ac9-5715-90fb-e0e74a817bb5"
		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#L333-L349"
		license_url = "https://github.com/eset/malware-ioc/blob/17baf44964a77368e9149f4f593eb098beddf1c5/LICENSE"
		logic_hash = "0e777f56136cd11d62abdf4f120410d5fe9cd522cfc06afbf085414a96279bf7"
		score = 75
		quality = 80
		tags = "FILE"
		license = "BSD 2-Clause"
		version = "1"

	strings:
		$s1 = "POST http://%s/status.php?r=%d%d HTTP/1.1\x0d\nAccept: text/html, application/xhtml+xml, */*\x0d\nAccept-Language: en-us\x0d\nUser-Agent: %s\x0d\nContent-Type: application/x-www-form-urlencoded\x0d\nAccept-Encoding: gzip, deflate\x0d\nHost: %s\x0d\nContent-Length: %d\x0d\nConnection: Keep-Alive\x0d\nCache-Control: no-cache\x0d\n\x0d\n" ascii wide
		$s2 = "id=1&op=report&status="

	condition:
		uint16( 0 ) == 0x5a4d and all of them
}

Strings (2 patterns)

Identifier	Type	Value	Modifiers
$s1	text	"POST http://%s/status.php?r=%d%d HTTP/1.1\x0d\nAccept: text/html, application/xhtml+xml, /\x0d\nAccept-Language: en-us\x0d\nUser-Agent: %s\x0d\nContent-Type: …	ascii wide
$s2	text	"id=1&op=report&status="

Condition

uint16( 0 ) == 0x5a4d and all of them

In plain words (Heuristic)

The file must start with “MZ” — a Windows executable (PE).
All patterns in the rule must match.

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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: ca4ee437-5ac9-5715-90fb-e0e74a817bb5

Metadata

version	1

Tags:FILE

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