Auto patch Freemius vulnerability

patch-freemius.sh

#!/bin/bash

find /var/www/* -type f -name class-freemius.php | while read -r file; do
  after=0
  while true; do
    ((after++))
    line=$(grep -A${after} "function _set_db_option" "${file}" | tail -n 1)

    if [[ "${line}" =~ fs_request_get ]]; then
      sed --in-place -E "s/^(.*)(static function _set_db_option.*)$/\1\2\n\1    check_admin_referer( 'fs_set_db_option' );/" "${file}"
      echo "FIXED   - ${file}"
      break
    elif [[ "${line}" =~ check_admin_referer ]]; then
      echo "SAFE    - ${file}"
      break
    elif [[ ${after} -gt 5 ]]; then
      echo "TOO_FAR - ${file}"
      break
    fi
  done
done

A small script that tries to patch all vulnerable class-freemius.php files. If you want to deploy this using SSH you can use a base64 encoded version so you won't have to upload the script. If your websites are located in a different folder, change /var/www to the folder you have your sites in.

Create a base64 encoded version:

cat patch-freemius.sh | base64 --wrap=0

Run it on a server over SSH:

ssh -t example.com 'echo <base64_encoded_string> | base64 --decode | sudo bash'

If you want to store the output into a log file you can use:

ssh -t example.com 'echo <base64_encoded_string> | base64 --decode | sudo bash' | tee -a freemius.log