Description
They are not what you see. They are different. Believe me.
Download Attachments : yes_its_a_zip_file_withnosecurity.zip
Approach
Upon extracting the zip archive, we discovered two images, but one of them, a PNG was unusually large at 11MB. This raised suspicions that there may be something hidden or embedded within the file.
i used binwalk to extract it
┌──(kali㉿iasad)-[~/CTFs/VishwaCTF]
└─$ binwalk -e Get_It_2.png
DECIMAL HEXADECIMAL DESCRIPTION
--------------------------------------------------------------------------------
0 0x0 PNG image, 1920 x 1080, 8-bit/color RGBA
26927 0x692F Zip archive data, at least v2.0 to extract
11276693 0xAC1195 name: Its_a_Morse_not_a_joke_take_it_seriously.wav
I attempted to decrypt .wav containing Morse code using Morse Decoder
, and here are the results.
After deciphering the Morse code. it instructed me to reverse the audio and identify the protagonist. Therefore, I used Audio Reverser
to reverse the file. upon listening to the reversed audio, I discovered that it was a scene from the TV series Lucifer. I entered the flag as vishwaCTF{lucifer} but it was rejected.
Next, I searched for any hidden data using steghide with the passphrase “lucifer” and discovered some hints.
┌──(kali㉿iasad)-[~/CTFs/VishwaCTF]
└─$ steghide extract -sf Its_a_Morse_not_a_joke_take_it_seriously.wav
Enter passphrase:
wrote extracted data to "nothing.txt".
cat nothing.txt
There is nothing here
listen it carefully
You should check the another picture(is it really a png)
And i want to tell you a story :
Once upon a time i got a name and it was password of something i was listening.
soo just listen it carefully.
Although steghide doesn’t support PNG files, the hint suggested that the file might not actually be a PNG. As I knew that there is a WAV file embedded in PNG Therefore, I attempted to use steghide on the WAV file instead, with the passphrase “lucifer.” I was successful in extracting the flag format.
┌──(kali㉿iasad)-[~/CTFs/VishwaCTF]
└─$ steghide extract -sf Its_a_Morse_not_a_joke_take_it_seriously.wav
Enter passphrase:
wrote extracted data to "flag.txt"
cat flag.txt
Nice
The flag is {the name of protagonist_S01E03}.
name of protagonist should be in small case.
the name of the protagonist is lucifer so the flag will be {lucifer_S01E03}
Flag: vishwaCTF{lucifer_S01E03}