St3g0

Challenge

Download this image and find the flag.

• Download image

Solution

Using zsteg on the image by running zsteg pico.flag.png produces the flag in the output:

b1,r,lsb,xy         .. text: "~__B>wV_G@"
b1,rgb,lsb,xy       .. text: "picoCTF{7h3r3_15_n0_5p00n_96ae0ac1}$t3g0"
b1,abgr,lsb,xy      .. text: "E2A5q4E%uSA"
b2,b,lsb,xy         .. text: "AAPAAQTAAA"
b2,b,msb,xy         .. text: "HWUUUUUU"
b2,a,lsb,xy         .. file: Matlab v4 mat-file (little endian) >\004<\305P, numeric, rows 0, columns 0
b2,a,msb,xy         .. file: Matlab v4 mat-file (little endian) | <\243, numeric, rows 0, columns 0
b3,r,lsb,xy         .. file: gfxboot compiled html help file
b4,r,lsb,xy         .. file: Targa image data (16-273) 65536 x 4097 x 1 +4352 +4369 - 1-bit alpha - right "\021\020\001\001\021\021\001\001\021\021\001"
b4,g,lsb,xy         .. file: 0420 Alliant virtual executable not stripped
b4,b,lsb,xy         .. file: Targa image data - Map 272 x 17 x 16 +257 +272 - 1-bit alpha "\020\001\021\001\021\020\020\001\020\001\020\001"
b4,bgr,lsb,xy       .. file: Targa image data - Map 273 x 272 x 16 +1 +4113 - 1-bit alpha "\020\001\001\001"
b4,rgba,lsb,xy      .. file: Novell LANalyzer capture file
b4,rgba,msb,xy      .. file: Applesoft BASIC program data, first line number 8
b4,abgr,lsb,xy      .. file: Novell LANalyzer capture file

See this general steganography guide for a good steganography workflow/checklist.

Flag

picoCTF{7h3r3_15_n0_5p00n_96ae0ac1}