How to remove the password from a PDF?

The easiest way GUI (recommended for novice)

Open the protected file and use ctrl+p or use print option to print the file, now save the file as pdf.


Using Command line

If you have pdftk already installed you can skip step1

Step 0: To check if Pdftk is already installed

sudo apt list | grep pdftk 

If output contains '[installed]' tag with pdftk then you can skip step1 i.e if the output is like this

pdftk/xenial 2.02-4 amd64 [installed]

Step 1: Install pdftk

sudo apt-get install pdftk

Step 2: Run following command

pdftk /path/to/input.pdf input_pw <yourpassword> output out.pdf


If you don't want to install pdftk there is another utility qpdf which is automatically installed (at least on 16.04 which I am using)

To use qpdf for generating unsecured pdf run following command.

qpdf -password=<your-password> -decrypt /path/to/secured.pdf out.pdf

For detailed information take a look at this HTG tutorial


I tried this in ubuntu mate 19.04:

sudo apt-get install qpdf
qpdf --password=YOURPASSWORD-HERE --decrypt input.pdf output.pdf

Source


sudo apt-get install pdftk
pdftk input.pdf output output.pdf user_pw YOURPASSWORD-HERE

This takes your input.pdf, removes the passwords and exports it as output.pdf.

You may want to take a look here to explore additional mehods.