Xenonminer's Website

hsctf 8 2021

My Solves/Writeups

Misc

Challenge Name Difficulty Points Writeup
misc/LSBlue Medium 220 jump

Web

Challenge Name Difficulty Points Writeup
web/NRC Easy 107 jump

Writeups

misc/LSBlue

Orca watching is an awesome pastime of mine!

Attachments: https://github.com/wackersCTF/hsctf-8/blob/main/misc/LSBlue/lsblue.png?raw=true

Solution

First, you will obtain the file they gave.

Since the title name of the challenge is LSBlue you will know that it has something to do with LSB.

The tool you will want to use for this challenge is zsteg. Zsteg is a Ruby tool that detects hidden data in PNG and BMP images.

Once you use zsteg on the original image file they gave, you will see many lines.

imagedata           .. text: "Uhv4BR$.<!(2#(0\"(2#*4*4@;L\\l"
b1,b,lsb,xy         .. text: "flag{0rc45_4r3nt_6lu3_s1lly_4895131}"
b2,r,lsb,xy         .. text: "UUTFUUUW"
b2,g,lsb,xy         .. file: PGP Secret Key -
b2,g,msb,xy         .. text: "iiUueUUu"
b2,b,msb,xy         .. text: "TUUUEUTAUE"
b2,bgr,msb,xy       .. text: "VU_UUUUeY"
b4,r,lsb,xy         .. text: "UEUffufffgUfffeeEfUVVuVeUUfVffUUVfvvDffVfUUWeFfVfUfeeUeVffUeWffwffeVffeffVfefffvfUEeffffeUgUUUffVeVeUUVfffUfUfeUWvffVefefUfvfgUUVffgeUvfUUfgffeVeVgfffUUUUUUUUUUUVehveUfUVfegeUUUUVgeUVggeUUUUUUUUUUUeVgvVUUUvUEUVvVuUUUfeUUUVvfVffffVfffeVfgeUUUUUUUVffeUUUUVeV"
b4,r,msb,xy         .. text: "jfnn\"ffjf"
b4,g,lsb,xy         .. text: "\"\"\"\"\"\"\"2"
b4,g,msb,xy         .. text: "DHDDDDDDDL"
b4,b,msb,xy         .. text: "7swwwww73sw337s73swww7swwww7w7773www77sww7swwww7swwwwwwwwswwsw7swwwsw7s7ww77sswwwww7wwwww7sww7333s333swww7333s7s"

Most of these lines are pretty unimportant, but in the second line you will get the flag. flag{0rc45_4r3nt_6lu3_s1lly_4895131}

web/NRC

Find the flag :)

Attachments: https://no-right-click.hsc.tf

Solution

Press Ctrl + Shift + I to open the developer console

Go to sources, then go to the CSS file

Look in the comments :)

Flag: flag{keyboard_shortcuts_or_taskbar}