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EMBEERESEARCH_Win_Mystic_Stealer_Bytecodes_Sep_2023

No description has been set in the source file - EmbeeResearch

MalwareMysticMystic StealerEmbee ResearchDetection Rule License 1.1Compiles with YARA-X (with warnings)
Author
Matthew @ Embee_reserch
Date
2023-09-21
Modified
2023-11-12
Score / Quality
75 / 75

What this rule detects

No description has been set in the source file - EmbeeResearch

Associated malware family: Mystic, Mystic Stealer.

It defines 13 patterns (0 text, 13 hex, 0 regex).

YARA-X says: warning[duplicate_pattern_value]: duplicate pattern value

Summary generated from the rule's metadata and condition.

Rule source

win-mystic-stealer-bytecodes-sep-2023.yarDetection Rule License 1.1
rule EMBEERESEARCH_Win_Mystic_Stealer_Bytecodes_Sep_2023
{
	meta:
		description = "No description has been set in the source file - EmbeeResearch"
		author = "Matthew @ Embee_reserch"
		id = "ef7c51e1-9c8c-5b66-bc1e-f35a796c84f2"
		date = "2023-09-21"
		modified = "2023-11-12"
		reference = "https://github.com/embee-research/Yara-detection-rules/"
		source_url = "https://github.com/embee-research/Yara-detection-rules//blob/ac56d6f6fd2a30c8cb6e5c0455d6519210a8b0f4/Rules/win_mystic_stealer_bytecodes_sep_2023.yar#L1-L29"
		license_url = "N/A"
		hash = "ef9fce75334befe0b435798c0b61dab1239ea5bc62b97654943676dd96dc6318"
		hash = "36d8cb1447e2c5da60d2b86bf29856919c25f8e71a17f1d0d61d03c5e0505e4b"
		hash = "e907c22288dacb37efa07481fef7a0d4ec0ce42954f12b2572ea7f5ffeecf313"
		logic_hash = "f68b6ef307e48b7ff6f944cfcf9c906a83611400af5af7d8621227874356960d"
		score = 75
		quality = 75
		tags = ""

	strings:
		$s1 = {99 d3 d8 c5}
		$s2 = {99 b7 66 df}
		$s3 = {cb 45 92 f8}
		$s4 = {7b cc e1 54}
		$s5 = {7b 9c 29 17}
		$s6 = {01 c4 fb 83}
		$s7 = {b6 0f 74 e3}
		$s8 = {93 58 b5 ee}
		$s9 = {81 d9 df be}
		$s10 = {7b d8 62 00}
		$s12 = {81 d9 df be}
		$s13 = {7b d8 62 00}
		$s14 = {77 4a bc ac}

	condition:
		( all of them )
}

Strings (13 patterns)

IdentifierTypeValueModifiers
$s1hex{99 d3 d8 c5}
$s2hex{99 b7 66 df}
$s3hex{cb 45 92 f8}
$s4hex{7b cc e1 54}
$s5hex{7b 9c 29 17}
$s6hex{01 c4 fb 83}
$s7hex{b6 0f 74 e3}
$s8hex{93 58 b5 ee}
$s9hex{81 d9 df be}
$s10hex{7b d8 62 00}
$s12hex{81 d9 df be}
$s13hex{7b d8 62 00}
$s14hex{77 4a bc ac}

Condition

( all of them )

In plain words (Heuristic)

  • All patterns in the rule must match.

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References

Sample hashes

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

  • ef9fce75334befe0b435798c0b61dab1239ea5bc62b97654943676dd96dc6318
  • 36d8cb1447e2c5da60d2b86bf29856919c25f8e71a17f1d0d61d03c5e0505e4b
  • e907c22288dacb37efa07481fef7a0d4ec0ce42954f12b2572ea7f5ffeecf313

Licence & attribution

Author: Matthew @ Embee_reserch

Source repository: Embee Research @ ac56d6f6fd

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: ef7c51e1-9c8c-5b66-bc1e-f35a796c84f2