SUSP_Base64_Encoded_Hex_Encoded_Code

YARA detection rule by Florian Roth (Nextron Systems) · NOASSERTION

Detects hex encoded code that has been base64 encoded

rule SUSP_Base64_Encoded_Hex_Encoded_Code {
   meta:
      author = "Florian Roth (Nextron Systems)"
      description = "Detects hex encoded code that has been base64 encoded"
      date = "2019-04-29"
      score = 65
      reference = "https://www.nextron-systems.com/2019/04/29/spotlight-threat-hunting-yara-rule-example/"
      id = "2cfd278f-ff45-5e23-b552-dad688ab303b"
   strings:
      $x1 = { 78 34 4e ?? ?? 63 65 44 ?? ?? 58 48 67 }
      $x2 = { 63 45 44 ?? ?? 58 48 67 ?? ?? ?? 78 34 4e }

      $fp1 = "Microsoft Azure Code Signp$"
   condition:
      1 of ($x*) and not 1 of ($fp*)
}

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

40bc287f-b133-4771-9178-2259fb133ba2

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

[[ reason ]]

What does this mean?

Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

[[ reason ]]

What do these messages mean?

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

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