Didier Stevens

Monday 28 November 2016

Update: pdf-parser Version 0.6.6

Filed under: Uncategorized — Didier Stevens @ 0:00

This new version of pdf-parser is a bugfix for /FLATEDECODE.

pdf-parser_V0_6_6.zip (https)
MD5: 47326468E1B5A1AF7BB8AD63688804D9
SHA256: 51C9B25B939B135D9949E51463F58ECEC0BEBEFB9C0EAA0B93326CBFB4D8F061

Monday 21 November 2016

Update: base64dump.py Version 0.0.5

Filed under: My Software,Uncategorized — Didier Stevens @ 0:00

This new version supports different encodings besides base64 (but the name remains base64dump).

The new encodings are hexadecimal (hex), \u unicode (bu) and %u unicode (pu).

Here’s an example with escaped unicode in JavaScript (%u), namely a PDF with shellcode in JavaScript:

20161118-221959

The shellcode, escaped with %u, can be extracted with base64dump:

20161118-222032

20161118-222049

There’s also a new option to do a string dump: -S

20161118-222059

And a last small update: this version also counts unique bytes, i.e. the number of different byte values found in the data.

base64dump_V0_0_5.zip (https)
MD5: 7AACFD3E34FEAAF41897F60FBC5279A3
SHA256: B4AB7B3A9D2947F08C6CC94F88CD825C9B2B63EE65AF7475E66BE9565EC4337A

Monday 30 November 2015

Update: Authenticode Tools

Filed under: Uncategorized — Didier Stevens @ 0:00

I released new versions of my AnalyzePESig and ListModules authenticode tools.

Extra fields with information were added to the output of the tools, and the tools were adapted to use the SE_BACKUP_NAME privilege, giving the tools the privilege to read files even when the permissions do not allow it (running as administrator and elevated).

A new field that might require some extra explanation is the DEROIDHash field. The DEROIDHash is a sha-256 hash of the DER structure and OID numbers of a PKCS7 signature: it’s the sha-256 hash of the bytes that make up the PKCS7 signature, except for the data. In other words, it’s the sha-256 hash of the DER bytes that specify the tags and the OID numbers. Signatures with the same structure and OID numbers share the same DEROIDhash.

For example, if a new version of a signed executable is released and the DEROIDHash value is different from the previous version, then the author has changed his/her signing process or is using a certificate with a different structure; or the executable was signed by another party using another signing process.

Thursday 31 July 2014

Videos

Filed under: Uncategorized — Didier Stevens @ 8:50

I plan to produce short videos more frequently. I will not post them all here on my blog, I’ve created another blog for all my videos:
videos.didierstevens.com.

The RSS is http://videos.didierstevens.com/feed/.

And from time to time, I’ll repost an old video on that feed.

Wednesday 14 March 2012

Update: PDFid And pdf-parser

Filed under: Uncategorized — Didier Stevens @ 9:15

To mark the occasion of my Malicious PDF Analysis workshop at Black Hat Europe 2012, I’m releasing version 0.0.12 of PDFiD and version 0.3.9 of pdf-parser.

The major change is that these 2 tools support Python 3 too now. And then there are a couple of bugfixes and new features given to me by readers.

You can find these tools on the PDF Tools page.

Tuesday 18 January 2011

Quickpost: Checking ASLR

Filed under: Quickpost,Uncategorized,Vulnerabilities,Windows 7,Windows Vista — Didier Stevens @ 11:13

Some people asked me for a simple way to check shell extensions for their ASLR support. You can do this with Process Explorer.

Start Process Explorer, and set the lower pane to display DLLs. Select process explorer.exe, and add column ASLR to the lower pane view. Then sort on column ASLR.

You will see this:

Notice that on a default Windows 7 32-bits install all DLLs (with code) support ASLR. The n/a is for resource DLLs, they don’t contain code, and ASLR doesn’t apply to them.

Now open an explorer window and right-click a file, like this:

This action will load the context menu shell extensions.

Take a look at Process Explorer:

Now you see the shell extensions without ASLR support.


Quickpost info


Tuesday 1 September 2009

Link: case of the tweep abduction

Filed under: Entertainment,Uncategorized — Didier Stevens @ 20:15

I know, I love a bit of mischief 😉

Wim renamed his “old” Twitter account @domgingelom to the “new” @wimremes. And then I promptly registered @domdingelom… 😉

Did some Tweeting under an assumed name…

And then gave the “new” @domdingelom to Wim.

Tuesday 8 July 2008

A Little Poll

Filed under: Uncategorized — Didier Stevens @ 20:45

According to you, what’s the single most-downloaded file from my site http://DidierStevens.com? It’s neither welcome.html nor robots.txt.

Post your guess as a comment.

Sunday 9 December 2007

Quickpost: Restoring Safe Mode with a .REG File for Windows 2000 SP4 Professional

Filed under: Uncategorized — Didier Stevens @ 11:00

I added the SafeBoot registry keys for Windows 2000 SP4 Professional to the zip file and updated the post.


Quickpost info


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