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YARA · ESET malware-ioc

ESET_Apt_Windows_TA410_Lookback_Magic

Matches message header creation in LookBack.

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 message header creation in LookBack.

Associated malware family: Lookback.

Targets: Windows PE.

It defines 1 patterns (0 text, 1 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

apt-windows-ta410-lookback-magic.yarBSD 2-Clause License
rule ESET_Apt_Windows_TA410_Lookback_Magic : FILE
{
	meta:
		description = "Matches message header creation in LookBack."
		author = "ESET Research"
		id = "5a40a307-772b-5600-9e58-f4bc6dfe6711"
		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#L351-L377"
		license_url = "https://github.com/eset/malware-ioc/blob/17baf44964a77368e9149f4f593eb098beddf1c5/LICENSE"
		logic_hash = "442a08a77fd2db03e507c0d5a32b17ab4e5936a209f7af23ef3c33a4b9f3d0d5"
		score = 75
		quality = 80
		tags = "FILE"
		license = "BSD 2-Clause"
		version = "1"

	strings:
		$s1 = {
            C7 03 C2 2E AB 48           //mov dword ptr [ebx], 0x48ab2ec2
            ( A1 | 8B 15 ) ?? ?? ?? ??      //mov (eax | edx), x
            [0-1]               //push ebp
            89 ?3 04            //mov dword ptr [ebc + 4], reg
            8B 4? 24 ??             //mov reg, dword ptr [esp + X]
            89 4? 08            //mov dword ptr [ebx + 8], ??
            89 ?? 0C            //mov dword ptr [ebx + 0xc], ??
            8B 4? 24 ??             //mov reg, dword ptr [esp + X]
            [1-2]               //push 1 or 2 args
            E8 ?? ?? ?? ??          //call
        }

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

Strings (1 patterns)

IdentifierTypeValueModifiers
$s1hex{ C7 03 C2 2E AB 48 //mov dword ptr [ebx], 0x48ab2ec2 ( A1 | 8B 15 ) ?? ?? ?? ?? //mov (eax | edx), x [0-1] …

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

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”

Copyright notice: Copyright (c) 2014-2018 ESET spol. s r.o.

Original rule

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

Rule id: 5a40a307-772b-5600-9e58-f4bc6dfe6711

Metadata

version1

Tags:FILE

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