9 replies to this topic

[Holmes.Sherlock]

This is an unsolved challenge from dCTF 2011. So, I don't know the solution. You try & share with us.

Attached Files

•  Challenge #8.zip   922bytes   45 downloads

[Icecube]

This is an unsolved challenge from dCTF 2011. So, I don't know the solution. You try & share with us.

I found it very fast. Probably, I had a lucky day.

The answer is:

Spoiler

pi ()

How to solve:
Step 1:

Spoiler

The file is a png file, so rename to PNG.

Step 2:

Spoiler

I used the GIMP to manipulate the PNG.

Step 3:

Spoiler

Layer ==> Mask ==> Add Layer Mask ...
Transfer layer's alpha channel (will show you pi in the preview)
Fill background with white and save the picture.

View end result:

Spoiler

 Challenge #8 - solution.png   4.54KB   10 downloads

[pscEx]

The Pi was my first answer in the contest. And that had not been accepted.
We tried with 3.14 (and more digits) > not accepted.

We tried with "Circle number" and similar > not accepted.

But maybe this helps, when the TEAM works on it:

When you floodfill the black and the red areas with white, about 20 red pixels remain.

I have no opinion about them. Maybe somebody else ...

Peter

[Holmes.Sherlock]

I found it very fast. Probably, I had a lucky day.

Sorry, I had to mention those additional trial & errors that we have already faced as mentioned by pscEx.


BTW, can anyone explain me the fact that we I I open the PNG in Microsoft Office Picture Manager or Picassa, I can see nothing. But, the PI symbol is visible is the file is opened in MSPaint or applied Paint.Net's Steganography plugin on it.

[Icecube]

We tried with 3.14 (and more digits) > not accepted.

Did you try with the same number of digits as there are points (33 if I counted them right)?
33 digits in total or 33 digits after the decimal point.

[Wonko the Sane]

Hey peeps, take a break and get some pie

Spoiler

..and yes, it is a low-precision pie, only going upt to 27 decimal digits....

Wonko

[pscEx]

Did you try with the same number of digits as there are points (33 if I counted them right)?
33 digits in total or 33 digits after the decimal point.

Interesting!
A different idea: What about "Code is 33"?

Is there still any possibility to check the correct code input?

Peter

[pscEx]

Hey peeps, take a break and get some pie

Spoiler

..and yes, it is a low-precision pie, only going upt to 27 decimal digits....

Wonko

Peter

[Holmes.Sherlock]

Hey peeps, take a break and get some pie

Spoiler

..and yes, it is a low-precision pie, only going upt to 27 decimal digits....

Do u spend half the time of the day to find images to put in spoilers?

[Wonko the Sane]

Do u spend half the time of the day to find images to put in spoilers?

Naah, only a few minutes (I'm pretty fast you know ... )

Apropos :

Spoiler

Wonko