Encrypt/Decrypt PDF files in any platform without installing anything but docker.

Build image

docker build -t crochik/pdfbox .

Encrypt file

docker run -it -v $PWD:/home crochik/pdfbox Encrypt -U <password> -keyLength 256 <input> <output>

Decrypt file

docker run -it -v $PWD:/home crochik/pdfbox Decrypt -password <password> <input> <output>