Okay, since someone actually downvoted both of my comments, I'll point out that libgpgme is a common encryption library that calls /usr/bin/gpg. Fortunately it uses execv(), but that leaves the environment unchanged so if anything further down the chain uses Bash it's still vulnerable.

I'll also provide a list of files from /usr/bin that are actually implemented using Bash (from a Linux Mint system). Anything using these with user-controlled environment variable values is vulnerable:

    $ grep -nR '#!.*bash' * | grep :1:
    apg:1:#!/bin/bash
    aptitude-create-state-bundle:1:#!/bin/bash
    aptitude-run-state-bundle:1:#!/bin/bash
    banshee:1:#!/usr/bin/env bash
    cautious-launcher:1:#!/bin/bash
    checkinstall:1:#!/bin/bash
    cinnamon2d:1:#!/bin/bash
    dns-fix:1:#!/bin/bash
    editdiff:1:#!/bin/bash
    fakenect:1:#!/bin/bash
    fakeroot:1:#!/bin/bash
    fakeroot-sysv:1:#!/bin/bash
    fakeroot-tcp:1:#!/bin/bash
    gnome-www-browser:1:#!/bin/bash
    google-chrome:1:#!/bin/bash
    google-chrome-stable:1:#!/bin/bash
    gufw-pkexec:1:#!/bin/bash
    im-config:1:#!/bin/bash -e
    init-checkconf:1:#!/bin/bash
    installwatch:1:#!/bin/bash
    inxi:1:#!/bin/bash
    itweb-settings:1:#!/bin/bash
    javaws:1:#!/bin/bash
    lcf:1:#!/bin/bash
    ldd:1:#! /bin/bash
    libtool:1:#! /bin/bash
    lua2dox_filter:1:#!/bin/bash
    lzcmp:1:#!/bin/bash
    lzdiff:1:#!/bin/bash
    lzegrep:1:#!/bin/bash
    lzfgrep:1:#!/bin/bash
    lzgrep:1:#!/bin/bash
    lzless:1:#!/bin/bash
    lzmore:1:#!/bin/bash
    mate-help:1:#!/bin/bash
    mintBackup:1:#!/bin/bash
    mint-fortune:1:#!/bin/bash
    mintupload:1:#!/bin/bash
    mintupload-manager:1:#!/bin/bash
    muinshee:1:#!/usr/bin/env bash
    mysqld_safe:1:#!/bin/bash
    p7zip:1:#!/bin/bash
    pipelight-plugin:1:#!/usr/bin/env bash
    pnmindex:1:#!/bin/bash
    policyeditor:1:#!/bin/bash
    ppmquantall:1:#!/bin/bash
    rarian-sk-config:1:#!/bin/bash
    rarian-sk-extract:1:#!/bin/bash
    rarian-sk-rebuild:1:#!/bin/bash
    rarian-sk-update:1:#!/bin/bash
    scrollkeeper-config:1:#!/bin/bash
    scrollkeeper-extract:1:#!/bin/bash
    scrollkeeper-rebuilddb:1:#!/bin/bash
    scrollkeeper-update:1:#!/bin/bash
    sotruss:1:#! /bin/bash
    steam:1:#!/usr/bin/env bash
    su-to-root:1:#!/bin/bash
    tomboy:1:#!/usr/bin/env bash
    tzselect:1:#!/bin/bash
    ucf:1:#!/bin/bash
    ucfr:1:#! /bin/bash
    usb-devices:1:#!/bin/bash
    X11/scrollkeeper-config:1:#!/bin/bash
    X11/fakenect:1:#!/bin/bash
    X11/lzgrep:1:#!/bin/bash
    X11/cautious-launcher:1:#!/bin/bash
    X11/xzdiff:1:#!/bin/bash
    X11/aptitude-create-state-bundle:1:#!/bin/bash
    X11/mint-fortune:1:#!/bin/bash
    X11/mate-help:1:#!/bin/bash
    X11/scrollkeeper-extract:1:#!/bin/bash
    X11/fakeroot:1:#!/bin/bash
    X11/editdiff:1:#!/bin/bash
    X11/lzdiff:1:#!/bin/bash
    X11/apg:1:#!/bin/bash
    X11/mintupload-manager:1:#!/bin/bash
    X11/gnome-www-browser:1:#!/bin/bash
    X11/ucfr:1:#! /bin/bash
    X11/lzcmp:1:#!/bin/bash
    X11/libtool:1:#! /bin/bash
    X11/im-config:1:#!/bin/bash -e
    X11/xzmore:1:#!/bin/bash
    X11/mintupload:1:#!/bin/bash
    X11/xzegrep:1:#!/bin/bash
    X11/javaws:1:#!/bin/bash
    X11/xchat-systray:1:#!/bin/bash
    X11/itweb-settings:1:#!/bin/bash
    X11/dns-fix:1:#!/bin/bash
    X11/su-to-root:1:#!/bin/bash
    X11/checkinstall:1:#!/bin/bash
    X11/usb-devices:1:#!/bin/bash
    X11/rarian-sk-extract:1:#!/bin/bash
    X11/tzselect:1:#!/bin/bash
    X11/google-chrome-stable:1:#!/bin/bash
    X11/xzcmp:1:#!/bin/bash
    X11/xzgrep:1:#!/bin/bash
    X11/pipelight-plugin:1:#!/usr/bin/env bash
    X11/lcf:1:#!/bin/bash
    X11/scrollkeeper-rebuilddb:1:#!/bin/bash
    X11/banshee:1:#!/usr/bin/env bash
    X11/cinnamon2d:1:#!/bin/bash
    X11/xzfgrep:1:#!/bin/bash
    X11/muinshee:1:#!/usr/bin/env bash
    X11/lzfgrep:1:#!/bin/bash
    X11/mintBackup:1:#!/bin/bash
    X11/tomboy:1:#!/usr/bin/env bash
    X11/fakeroot-sysv:1:#!/bin/bash
    X11/aptitude-run-state-bundle:1:#!/bin/bash
    X11/gufw-pkexec:1:#!/bin/bash
    X11/init-checkconf:1:#!/bin/bash
    X11/x-www-browser:1:#!/bin/bash
    X11/lzegrep:1:#!/bin/bash
    X11/rarian-sk-update:1:#!/bin/bash
    X11/sotruss:1:#! /bin/bash
    X11/ldd:1:#! /bin/bash
    X11/ppmquantall:1:#!/bin/bash
    X11/rarian-sk-rebuild:1:#!/bin/bash
    X11/xzless:1:#!/bin/bash
    X11/rarian-sk-config:1:#!/bin/bash
    X11/p7zip:1:#!/bin/bash
    X11/google-chrome:1:#!/bin/bash
    X11/lzmore:1:#!/bin/bash
    X11/fakeroot-tcp:1:#!/bin/bash
    X11/mysqld_safe:1:#!/bin/bash
    X11/ucf:1:#!/bin/bash
    X11/policyeditor:1:#!/bin/bash
    X11/lzless:1:#!/bin/bash
    X11/lua2dox_filter:1:#!/bin/bash
    X11/installwatch:1:#!/bin/bash
    X11/inxi:1:#!/bin/bash
    X11/scrollkeeper-update:1:#!/bin/bash
    X11/steam:1:#!/usr/bin/env bash
    X11/pnmindex:1:#!/bin/bash
    xchat-systray:1:#!/bin/bash
    x-www-browser:1:#!/bin/bash
    xzcmp:1:#!/bin/bash
    xzdiff:1:#!/bin/bash
    xzegrep:1:#!/bin/bash
    xzfgrep:1:#!/bin/bash
    xzgrep:1:#!/bin/bash
    xzless:1:#!/bin/bash
    xzmore:1:#!/bin/bash