22 lines
748 B
Text
22 lines
748 B
Text
rule SUSP_certificate_payload {
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meta:
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description = "Detects payloads that pretend to be certificates"
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date = "2018/08/02"
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author = "Didier Stevens, Florian Roth"
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reference = "https://blog.nviso.be/2018/08/02/powershell-inside-a-certificate-part-3/"
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score = 50
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id = "6f1fe410-591a-5a59-a683-67cad9777dfe"
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strings:
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$re1 = "-----BEGIN CERTIFICATE-----"
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$fp1 = "replace it with the PEM-encoded root certificate"
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condition:
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uint32(0) == 0x2D2D2D2D
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and $re1 at 0
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/* not 'M' at position 29, which is after the BEGIN CERTIFICATE header plus line break */
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/* \r\n */
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and not uint8(29) == 0x4D
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/* \n */
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and not uint8(28) == 0x4D
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and not 1 of ($fp*)
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}
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