20 lines
704 B
Text
20 lines
704 B
Text
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rule WEBSHELL_ASPX_XslTransform_Aug21 {
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meta:
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author = "Max Altgelt"
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reference = "https://gist.github.com/JohnHammond/cdae03ca5bc2a14a735ad0334dcb93d6"
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date = "2020-02-23"
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description = "Detects an ASPX webshell utilizing XSL Transformations"
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id = "44254084-a717-59e6-a3ac-eca3c1c864a8"
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strings:
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$csharpshell = "Language=\"C#\"" nocase
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$x1 = "<root>1</root>"
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$x2 = ".LoadXml(System.Text.Encoding.UTF8.GetString(System.Convert.FromBase64String("
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$s1 = "XsltSettings.TrustedXslt"
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$s2 = "Xml.XmlUrlResolver"
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$s3 = "FromBase64String(Request[\""
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condition:
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filesize < 500KB and $csharpshell and (1 of ($x*) or all of ($s*))
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}
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