Steganography - Let's Race

What car-turned-hippie in "Cars" shares its namesake with a San Francisco district known for its countercultural history?

Solution :

We got a Letsgoo.zip attached with the challenge and we need a password to crack this. Looking at the description we got to know that the character from Cars was “fillmore”.

Unzipped using this password with WinRAR and got a doc.txt and an AVIF image file.

Doc.txt had this

The image also shows three positions of cars in a race. So, this is the clue.

For the image, I got no useful information from strings, zsteg, foremost, exiftool etc and other steg tools like stegseek, stegsnow, steghide etc…

Therefore, I opened the image in Stegsolve, a a java based steganography tool which can be used to extract data, set bit plane colors, lsb, msb and view images in our desired way.

Using stegsolve I opened data extract mode and tried the positions of cars in the bit planes as displayed in the image. First, I tried red, blue and green – got nothing. Then tried Red, Green and Blue – the preview just displayed the flag

Flag: ViswaCTF{1_l0v3_C0r5}