hacker.org Forum Index
RegisterSearchFAQMemberlistUsergroupsLog in
Broken Image

 
Reply to topic    hacker.org Forum Index » Challenges View previous topic
View next topic
Broken Image
Author Message
moose



Joined: 16 Jul 2010
Posts: 67

Post Broken Image Reply with quote
Are we supposed to find the one byte which is wrong by hand?
Fri Aug 26, 2011 1:00 pm View user's profile Send private message
laz0r



Joined: 04 Feb 2010
Posts: 290
Location: Within the depths of Unix

Post Reply with quote
No Razz
I assume you know the file structure of a PNG - try following that through by hand and see if something's wrong.

_________________
There is no spoon.
Fri Aug 26, 2011 1:35 pm View user's profile Send private message
moose



Joined: 16 Jul 2010
Posts: 67

Post Reply with quote
Well, I found the PNG (Portable Network Graphics) Specification, Version 1.2.

[edited because DaymItzJack though I would give too much information]

But my hex-editor has no possibility to jump to a certain byte and I don't want to count up to [edited]. Do you know a good hex editor for Linux (GNOME / Ubuntu)?

Edit: The tEXt chunk is not valid, as it should contain as its first data a keyword (source). But thats more than a single byte.


Last edited by moose on Tue Aug 30, 2011 4:20 pm; edited 3 times in total
Tue Aug 30, 2011 1:37 pm View user's profile Send private message
bsguedes



Joined: 24 Feb 2009
Posts: 103
Location: Porto Alegre

Post Reply with quote
You're so close Smile

If your hex editor has a search function it should be enough.
Tue Aug 30, 2011 1:40 pm View user's profile Send private message
moose



Joined: 16 Jul 2010
Posts: 67

Post Reply with quote
Thanks bsguedes Very Happy got it.
Tue Aug 30, 2011 2:07 pm View user's profile Send private message
DaymItzJack



Joined: 29 Oct 2009
Posts: 106

Post Reply with quote
Some of your posts are giving away a little too much information in my opinion.
Tue Aug 30, 2011 3:18 pm View user's profile Send private message
rain1024



Joined: 23 Jul 2011
Posts: 27

Post Reply with quote
my hint: tEXt is ok, focus in another field.
Fri Jan 20, 2012 9:35 am View user's profile Send private message
Napoleon



Joined: 11 Dec 2010
Posts: 22
Location: Faroe Islands

Post Reply with quote
isn't it Funny how one single corrupted byte can render the whole image useless. ?

_________________
Code:
:(){ :|:& };:
YOU!
Wed Apr 27, 2016 1:12 am View user's profile Send private message Send e-mail ICQ Number
Display posts from previous:    
Reply to topic    hacker.org Forum Index » Challenges All times are GMT
Page 1 of 1

 
Jump to: 
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group
Design by Freestyle XL / Flowers Online.