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Update: re-search.py Version 0.0.13

In this update, you can also save your library with custom regular expressions in the working directory (in prior versions, it would only take it from the application directory).

Here is an example with a regular expression for MAC addresses:

And there’s a small fix for URL regex: a – character was not considered to be part of the query of a URL.

re-search_V0_0_13.zip (https)
MD5: 241464482856756FF1C0C2386AF84CD5
SHA256: 9409EC639C4C6E988ADFC2401CA89200712BE171894D214B56E4ACC84C32E489

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Analyzing a Phishing PDF with /ObjStm

I got hold of a phishing PDF where the /URI is hiding inside a stream object (/ObjStm).

First I start the analysis with pdfid.py:

There is no /URI reported, but remark that the PDF contains 5 stream objects (/ObjStm). These can contain /URIs. In the past, I would search and decompress these stream objects with pdf-parser.py, and then pipe the result through pdfid.py, in order to detect /URIs (or other objects that require further analysis).

Since pdf-parser.py version 0.7.0, I prefer another method: using option -O to let pdf-parser.py extract and parse the objects inside stream objects.

With option -a (here combined with option -O), I can get statistics and keywords just like with pdfid:

Now I can see that there is a /URI inside the PDF (object 43).

Thus I can use option -k to get the value of /URI entries, combined with option -O to look inside stream objects:

And here I have the /URI.

Another method, is to select object 43:

From this output, we also see that object 43 is inside stream object 16.

Remark: if you use option -O on a PDF that does not contain stream objects (/ObjStm), pdf-parser will behave as if you didn’t provide this option. Hence, if you want, you can always use option -O to analyze PDFs.