Here is a tiny file that you might find fun to do while cramming other forms of knowledge in your head. :D
All the best for your exams.
- Flag Format: /flag{.+}/
Provided text.bmp
Solution
This is a simple question meant to be a refresher while the examinations are going on.
This does not show anything other than the fact that most of the file is empty. Which actually makes the job easier. On opening the file in binary mode, we confirm this.
00000000: 424d 6675 0000 0000 0000 3600 0000 2800 BMfu......6...(.
00000010: 0000 6400 0000 6400 0000 0100 1800 0000 ..d...d.........
00000020: 0000 3075 0000 c30e 0000 c30e 0000 0000 ..0u............
00000030: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000040: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000b40: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000b50: 0000 0000 0000 0000 7d50 3a00 0000 0000 ........}P:.....
00000b60: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000b70: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000b80: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000b90: 0000 0000 0000 0000 0000 0000 0000 0000 ................
00000ba0: 0000 0000 0000 0000 0000 0000 0000 0000 ................
...
00000e70: 0000 0000 0000 0000 0000 0000 0000 0000 ................
...
000074b0: 0000 0000 0000 0000 0000 0000 0000 0000 ................
000074c0: 0000 0000 0000 0000 0000 0000 0000 0000 ................
000074d0: 616c 6600 0000 0000 0000 0000 0000 0000 alf.............
000074e0: 0000 0000 0000 0000 0000 0000 0000 0000 ................
000074f0: 0000 0000 0000 0000 0000 0000 0000 0000 ................
...
However we also see some text scattered in the middle. Which seems interesting.
We try to read the data in the files.
$ cat text.bmp
BMfu6(dd0u}P:smroFynaMnIsemoCongetS{galf
That seems interesting enough. It simply the reversed string of our flag.
}P:smroFynaMnIsemoCongetS{galf
Flag
flag{StegnoComesInManyForms:P}
Recommended Reading
Lips Are Sealed
#ctf #gdb #introductory #reverseA mythical beast has broken through the magical community and is wreaking havoc in the human world. Shrenik was assigned to go and subdue the said beast, but in his haste, he forgot to ask what manner of beast it was. He asks me to tell it to him,...
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Foren-Steg
#ctf #forensics #stegno #zipFind the flag, flag finder.
- Flag Format: /flag{.+}/
Provided foren-steg.docx
Solution
The file provided to us appears to be a docx file. Let us see what happens when we try to open it.
There appears to be nothing in the file but gibberish...
...