A simple script build for Ubuntu to download and install the current version of GnuPG.

gnupg-updater.sh

#!/bin/bash
# ---------
# Script to build and install GnuPG 2.2.x

GNUPG='2.4.4'
LIBGPGERROR='1.47'
LIBGCRYPT='1.10.3'
LIBKSBA='1.6.5'
LIBASSUAN='2.5.6'
NTBTLS='0.3.2'
NPTH='1.6'
PINENTRY='1.2.1'

################################################################################

if [ "${LOGNAME}" != "root" ]; then
    printf "\33[0;31mThis script must be ran by the 'root' user, but was ran by the ${LOGNAME} instead.\033[0m\n"
    exit 1
fi

################################################################################

if [ -f /usr/local/bin/gpg ]; then
    OLDVER="`/usr/local/bin/gpg --version |grep gpg |awk '{ print $3 }'`"
else
    OLDVER="0"
fi

if [ "${GNUPG}" == "${OLDVER}" ]; then
    exit 0
fi

################################################################################

UPDATE=""
PACKETS="bzip2 make gettext texinfo gnutls-bin libgnutls28-dev build-essential libbz2-dev zlib1g-dev libncurses-dev libsqlite3-dev libldap2-dev libgnutls28-dev bzip2 make gettext texinfo gnutls-bin build-essential libbz2-dev zlib1g-dev libsqlite3-dev libldap2-dev libreadline-dev"
dpkg --get-selections |sed 's/:/ /g' |awk '{print $1}' > /tmp/installed-packages.txt

for a in $PACKETS
do
    if [ `egrep "^$a$" /tmp/installed-packages.txt |wc -l` != "1" ]; then
        echo "$a is not installed"
        UPDATE="$a $UPDATE"
    fi
done

rm -f /tmp/installed-packages.txt

if [ "$UPDATE" != "" ]; then
    apt update
    apt install -y $UPDATE
fi

################################################################################

echo "/usr/local/lib" > /etc/ld.so.conf.d/gpg2.conf && ldconfig
mkdir -p /var/src/gnupg

if [ -x /usr/bin/gpg ] || [ -x /usr/local/bin/gpg ]; then
    curl -Ls 'https://gnupg.org/signature_key.asc' -o /var/src/gnupg/signing-keys.asc
    if [ -x /usr/bin/gpg ]; then
        /usr/bin/gpg -k -qq > /dev/null
        /bin/sleep 0.5
        /usr/bin/gpg -qq --import /var/src/gnupg/signing-keys.asc
    else
        /usr/local/bin/gpg -k -qq > /dev/null
        /bin/sleep 0.5
        /usr/local/bin/gpg -qq --import /var/src/gnupg/signing-keys.asc
    fi
fi

echo "## Starting Gnupg Install"
for Package in libgpg-error-${LIBGPGERROR} libgcrypt-${LIBGCRYPT} libassuan-${LIBASSUAN} libksba-${LIBKSBA} ntbtls-${NTBTLS} npth-${NPTH} pinentry-${PINENTRY} gnupg-${GNUPG}
do
    if [ ! -d /var/src/gnupg ]; then mkdir -p /var/src/gnupg; fi
    cd /var/src/gnupg
    PackageDir="`echo "${Package}" |sed 's/[0-9]*//g' |sed 's/\.//g' |sed 's/-$//g'`"
    Skip="No"
    echo "Starting on ${Package}"
    if [ -d ${Package} ]; then
        echo -n " - Package found, checking:     "
        if [ -x /usr/bin/gpg ] || [ -x /usr/local/bin/gpg ]; then
            if [ -x /usr/local/bin/gpg ]; then
                /usr/local/bin/gpg -qq --verify ${Package}.tar.bz2.sig 2> /dev/null
                StatusVerify=${?}
            else
                /usr/bin/gpg -qq --verify ${Package}.tar.bz2.sig 2> /dev/null
                StatusVerify=${?}
            fi
            if [ ${StatusVerify} != "0" ]; then printf "\33[0;31m${Package} Failed to Verify\033[0m\n"; else Skip="Yes"; printf "\033[0;32mDone!\033[0m\n"; fi
        else
            Skip="Yes"
        fi
    fi
    if [ "${Skip}" != "Yes" ]; then
        cd /var/src/gnupg
        rm -rf ${Package}
        echo -n " - Downloading Package:         "
        wget -cq https://www.gnupg.org/ftp/gcrypt/${PackageDir}/${Package}.tar.bz2
        StatusDown=${?}
        if [ ${StatusDown} != "0" ]; then printf "\33[0;31m${Package} Failed to download\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
        echo -n " - Downloading Package Sign:    "
        wget -cq https://www.gnupg.org/ftp/gcrypt/${PackageDir}/${Package}.tar.bz2.sig
        StatusDownSig=${?}
        if [ ${StatusDownSig} != "0" ]; then printf "\33[0;31m${Package} Failed to download sign\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
        if [ -x /usr/bin/gpg ] || [ -x /usr/local/bin/gpg ]; then
            echo -n " - Verifing package"
            if [ -x /usr/local/bin/gpg ]; then
                echo -n ":            "
                /usr/local/bin/gpg -qq --verify ${Package}.tar.bz2.sig 2> /dev/null
                StatusVerify=${?}
            else
                echo -n " (via gpg):  "
                /usr/bin/gpg -qq --verify ${Package}.tar.bz2.sig 2> /dev/null
                StatusVerify=${?}
            fi
            if [ ${StatusVerify} != "0" ]; then printf "\33[0;31m${Package} Failed to Verify\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
        else
            echo " - Skipping package verification."
        fi
    fi
        echo -n " - UnTaring the package:        "
        tar -xjf ${Package}.tar.bz2
        StatusUntar=${?}
        if [ ${StatusUntar} != "0" ]; then printf "\33[0;31m${Package} Failed to UnTar\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
        echo -n " - Changing into the Directory: "
        cd /var/src/gnupg/${Package}
        StatusCD=${?}
        if [ ${StatusCD} != "0" ]; then printf "\33[0;31m${Package} Failed to change into the ${Package} directory\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
        if [ "${PackageDir}" == "pinentry" ]; then
            echo -n " - Running pinentry configure:  "
            ./configure --enable-pinentry-curses --disable-pinentry-qt4 > /dev/null 2> /dev/null
            StatusConfig=${?}
        else
            echo -n " - Running configure:           "
            ./configure > /dev/null 2> /dev/null
            StatusConfig=${?}
        fi
        if [ ${StatusConfig} != "0" ]; then printf "\33[0;31m${Package} Failed to run './configure'\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
        echo -n " - Running make:                "
        make > /dev/null 2> /dev/null
        StatusMake=${?}
        if [ ${StatusMake} != "0" ]; then printf "\33[0;31m${Package} Failed to run 'make'\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
        echo -n " - Running make check:          "
        make check > /dev/null 2> /dev/null
        StatusMakeCheck=${?}
        if [ ${StatusMakeCheck} != "0" ]; then printf "\33[0;31m${Package} Failed to run 'make check'\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
    echo -n " - Running make install:        "
    make install > /dev/null 2> /dev/null
    StatusMakeInstall=${?}
    if [ ${StatusMakeInstall} != "0" ]; then printf "\33[0;31m${Package} Failed to run 'make install'\033[0m\n"; exit 1; else printf "\033[0;32mDone!\033[0m\n"; fi
done
rm /usr/bin/gpg-agent; ln -s /usr/local/bin/gpg-agent /usr/bin/gpg-agent
rm /usr/bin/dirmngr; ln -s /usr/local/bin/dirmngr /usr/bin/dirmngr
echo -n "Killing old version of gnupg:   "
gpgconf --kill all
printf "\033[0;32mDone!\033[0m\n"
echo -n "Current version is: "
/usr/local/bin/gpg --version |head -1
echo "## Finished Gnupg Install"