Packages also had their own independent fixes and need updating. During the firmware update process the packages will be reinstalled properly. Otherwise, uninstall and then reinstall packages to ensure that the latest version of the binaries is in use.
Head on over to the download page to get the ISO/upgrade file: https://www.pfsense.org/download/
Check out the official post here: https://blog.pfsense.org/?p=1377