diff --git a/Malicious_Documents/PDF.yar b/Malicious_Documents/PDF.yar index 6c7c7d5..5852af0 100644 --- a/Malicious_Documents/PDF.yar +++ b/Malicious_Documents/PDF.yar @@ -51,6 +51,22 @@ rule suspicious_creation : PDF $magic at 0 and $header and 1 of ($create*) } +rule multiple_filtering : PDF +{ +meta: +author = "Glenn Edwards (@hiddenillusion)" +version = "0.2" +weight = 3 + + strings: + $magic = { 25 50 44 46 } + $attrib = /\/Filter.*(\/ASCIIHexDecode\W+|\/LZWDecode\W+|\/ASCII85Decode\W+|\/FlateDecode\W+|\/RunLengthDecode){2}/ + // left out: /CCITTFaxDecode, JBIG2Decode, DCTDecode, JPXDecode, Crypt + + condition: + $magic at 0 and $attrib +} + rule suspicious_title : PDF { meta: