17199 D3j4.rar Site
XCTF{d3j4_vu_st3g0_m4st3r} (or similar depending on the event year).
The RAR archive contains a single image file, typically named .
The "Deja Vu" hint often refers to the fact that the image's height has been tampered with to hide data at the bottom (a common CTF trope). 17199 d3j4.rar
Locate the 4-byte height value and increase it (e.g., from 00 00 02 00 to 00 00 04 00 ).
Use a hex editor (like HxD or 010 Editor) to view the PNG's IHDR chunk . Locate the 4-byte height value and increase it (e
Extract the contents of the RAR archive and find the hidden flag. 1. Extraction and Initial Analysis
By toggling through the bit planes (specifically Red Plane 0 , Green Plane 0 , or Blue Plane 0 ), a distorted or faint QR code becomes visible in the top-left corner. 3. Fixing the Image Dimensions (The "Deja Vu" Trick) Green Plane 0
The string found at the bottom of the image (after fixing the height) is often encoded in Base64 or ROT13 . 5. Flag Extraction Decoding the discovered string reveals the flag format:
