Big Zip | picoGym Exclusive Solutions

Description

Unzip this archive and find the flag.

Setup

Download the provided archive and unzip it somewhere you can recurse through easily.

Keep a terminal ready with grep/awk so you can interrogate thousands of files quickly.

wget https://artifacts.picoctf.net/c/503/big-zip-files.zip && \ unzip big-zip-files.zip && \ rm big-zip-files.zip

Step 1Fan out with grep
Recursively search for the picoCTF prefix; the archive is too large to inspect manually, but grep cuts straight to the hits.
grep -R pico
Pipe the results into other text utilities if you want to isolate the final word on each line.
Step 2Trim the noise
Every hit prints a full path plus surrounding text. Use additional tools to strip away the file path and metadata so the raw flag remains.
grep -R pico | grep -oE 'picoCTF\{.*\}' --color=none
grep -R pico | sed 's/.* //g'
Step 3Record the flag
Once only the picoCTF token remains, copy it out and you are done; no further decoding is necessary.

picoCTF{gr3p_15_m4g1c_ef87...}

Any recursive grep that isolates the final token reveals the exact flag as stored inside the archive.