2017-02-20: Finishing oxfoo1m3 crackme

On the last episode of Hacking Livestream (#10: Medium-hard RE challenge - see below) I've shown how to approach a medium-hard reverse-engineering challenge. The example I used was the oxfoo1m3 challenge found in the "Level5-professional_problem_to_solve" directory of crackmes.de archive (this one), which I picked using such complex criteria as "something that runs on Ubuntu" and "something 32-bit so people with the free version of IDA can open it". As expected (and defensively mentioned several time during the stream), I was not able to complete this challenge during the livestream itself (which is only one hour, and that includes news and updates, and Q&A). However I did finish the task two days ago. It turned out I was close to the goal - took only around 30 minutes of additional work (which makes me wonder if Level5 is actually close to an RE300 challenge; probably it's closer to RE200). Anyway, here is the promised part 2 of the solution.

Note 1: While I'll write down a short recap of the initial steps and discoveries, please take a look at the recording of the episode #10 for details (crackme starts at 15m40s). If you've already seen it, just jump to part 2 in the second half of this post.

Note 2: Since this post is meant to have some education value I'll assume that the readers have only basic knowledge on RE techniques, and therefore I'll try to be verbose on some topics which are most likely well known amongst the more senior folks.

Read more... [ 8 comments ]

2017-01-09: Garść newsów: DS top 2, Sekurak/Offline #3

DS top2, p4 top5Pierwsze newsy z nowego roku:

  • Dragon Sector zakończył sezon 2016 na drugim miejscu - czyli udało nam się powtórzyć rezultat z 2015 :). Trochę więcej rozpisałem się kilka dni temu na moim FB, więc wspomnę jedynie, że na piątym miejscu sezon zakończył inny polski zespół - p4 - gratulacje!
  • Wyszedł Sekurak/Offline #3, czyli darmowy e-zin o bezpieczeństwie (głównie webowym) prowadzony przez ekipę serwisu sekurak.pl. Link do linków ;)
Na ten moment tyle. "Słoniem w pokoju", jak to lubią mawiać nasi zachodni znajomi, jest pytanie kiedy kolejny stream - prawdopodobnie dopiero w następnym tygodniu, ale jeszcze zobaczymy jak wyjdzie.

Czytaj dalej... [ 2 komentarze ]

Five newest or recently updated notes (these are unfinished posts, code snippets, links or commands I find useful but always forget, and other notes that just don't fit on the blog):

Click here for a list of all notes.

EN Security papers and research notes

Some conference slides are linked at the bottom of this page.

EN Selected vulnerabilities

The full list of vulnerabilities discovered by me (including collaborative work) can be found here (please note that the list might be out of date).

The Google Application Security / Research site might also contain some of my findings.

EN Coding (selected posts)
EN Tools and libraries
  • PiXieServ is a simplified PXE (network boot) server for Windows and Linux-based OS, created for testing of very small home-made OS. See also the post about it.
  • ExcpHook, a system-wide exception monitor for Windows XP 32-bit. Useful if you're fuzzing something that doesn't like having a debugger attached.
  • Ent is an entropy measuring tool for reverse engineering reconnaissance (see also a post explaining how to use it).
  • HiperDrop is a simple command line process memory dumper for Windows, with a few different work modes.
  • asmloader - this little app executes headerless machine code (compiled assembly code). It's meant to be an aid in learning/teaching and playing with assembly, as well as the right tool when you just need to execute some machine code.
  • NetSock is a simple socket/networking lib/wrapper for C++ I've wrote back in 2003 and update from time to time - I use it for most of my network-enabled projects.
PL Videotutoriale i podcasty [ 0 views | 0 videos | 0 subscribers ]

Subscribe to me on YouTube W wolnym czasie prowadzę videocasty na żywo o programowaniu, reverse engineeringu oraz hackingu/security:

Livestream | Kanał na YT | Archiwum starszych odcinków

Najnowszy odcinek: Gynvael's Livestream: OSDev #5 (17.06.2016 19:00)
[ 38 thumbs up | 5 comments | 1 115 views ]

Dodatkowo: ReverseCraft - starsza seria podcastów o reverse engineeringu i assembly.

PL Edukacyjnie (wybrane posty)

Dla programistów:

Security / hacking:

  • Hacking - jak uczyć się security/hackingu i spać spokojnie.

Dodatkowo, kilka przemyśleń na temat odnajdywania się na rynku pracy w IT:

PL Programowanie (wybrane posty)

← trochę więcej postów jest po angielskojęzycznej stronie.

PL Gamedev i GFX (wybrane posty)

Grafika generowana proceduralnie:

【 design & art by Xa / Gynvael Coldwind 】 【 logo font (birdman regular) by utopiafonts / Dale Harris 】