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Diffstat (limited to 'source/x/xdg-utils/doinst.sh')
| -rw-r--r-- | source/x/xdg-utils/doinst.sh | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/source/x/xdg-utils/doinst.sh b/source/x/xdg-utils/doinst.sh new file mode 100644 index 00000000..4d72a961 --- /dev/null +++ b/source/x/xdg-utils/doinst.sh @@ -0,0 +1,100 @@ +#!/bin/sh +# Regarding xdg-open in /etc/mailcap: +# +# It turns out that xdg-open is not very smart about what it +# passes off control to, leading to security problems where (for +# example) a file could be provided on a web site as a PDF, but +# rather than send it to a PDF viewer, xdg-open sends it to kfmclient +# which uses a whole different set of criteria to determine what sort +# of file it is. It's trivial to make something that's detected as +# a PDF at first, but then is executed as a .desktop file later, +# resulting in the execution of arbitrary code as the user. +# +# This is not acceptable, and we see no way to fix it as long as +# xdg-open passes off the resolution of the file type (again) to +# something else. In light of the potential security risks, we +# will turn off the use of xdg-open if it appears to have been +# added by a previous version of the xdg-utils package. +# +# Vulnerability code: CVE-2009-0068 + +# First, we will detect an automatically modified mailcap by +# looking for the comment "# Sample xdg-open entries:" + +if [ -r etc/mailcap ]; then + if grep -q "^# Sample xdg-open entries:$" etc/mailcap ; then + + COOKIE=$(usr/bin/mcookie) + if [ -z $COOKIE ]; then + exit 1 + fi + + # First, add a space to the end of the comment used to detect this + # junk so that we won't detect it again (in case the user decides + # to enable this themselves later on -- their call). Add a warning + # about this type of xdg-open use being insecure. Finally, comment + # out any lines like this. + + echo "# Sample xdg-open entries: " > tmp/mailcap-$COOKIE + cat << EOF >> tmp/mailcap-$COOKIE +# +# NOTE: Using xdg-open in /etc/mailcap in this way has been +# shown to be insecure and is not recommended (CVE-2009-0068)! +# A remote attacker can easily make a filetype such as a +# .desktop script appear to xdg-open as a PDF file causing its +# arbitrary contents to be executed. Consider these to be +# examples of what NOT to do. The xdg-utils package no longer +# adds any lines such as these to /etc/mailcap. +# +EOF + cat etc/mailcap \ + | grep -v "# Sample xdg-open entries:" \ + | sed -e 's/^audio\/\*; \/usr\/bin\/xdg-open %s/#audio\/\*; \/usr\/bin\/xdg-open %s/g' \ + | sed -e 's/^image\/\*; \/usr\/bin\/xdg-open %s/#image\/\*; \/usr\/bin\/xdg-open %s/g' \ + | sed -e 's/^application\/msword; \/usr\/bin\/xdg-open %s/#application\/msword; \/usr\/bin\/xdg-open %s/g' \ + | sed -e 's/^application\/pdf; \/usr\/bin\/xdg-open %s/#application\/pdf; \/usr\/bin\/xdg-open %s/g' \ + | sed -e 's/^application\/postscript ; \/usr\/bin\/xdg-open %s/#application\/postscript ; \/usr\/bin\/xdg-open %s/g' \ + | sed -e 's/^text\/html; \/usr\/bin\/xdg-open %s ; copiousoutput/#text\/html; \/usr\/bin\/xdg-open %s ; copiousoutput/g' >> tmp/mailcap-$COOKIE + + cat tmp/mailcap-$COOKIE > etc/mailcap + rm -f tmp/mailcap-$COOKIE + + fi +fi + +## BEGIN (HERE IS WHAT CAUSED THIS MESS): + +## Add some reasonable default values for xdg-open to /etc/mailcap, +## since this is where many programs look for this information: +# +#if ! grep -q '# Sample xdg-open entries:' etc/mailcap 1> /dev/null 2> /dev/null ; then +# echo "# Sample xdg-open entries:" >> etc/mailcap +# echo >> etc/mailcap +#fi +#if ! grep -q 'audio/' etc/mailcap ; then +# echo 'audio/*; /usr/bin/xdg-open %s' >> etc/mailcap +# echo >> etc/mailcap +#fi +#if ! grep -q 'image/' etc/mailcap ; then +# echo 'image/*; /usr/bin/xdg-open %s' >> etc/mailcap +# echo >> etc/mailcap +#fi +#if ! grep -q 'application/msword' etc/mailcap ; then +# echo 'application/msword; /usr/bin/xdg-open %s' >> etc/mailcap +# echo >> etc/mailcap +#fi +#if ! grep -q 'application/pdf' etc/mailcap ; then +# echo 'application/pdf; /usr/bin/xdg-open %s' >> etc/mailcap +# echo >> etc/mailcap +#fi +#if ! grep -q 'application/postscript' etc/mailcap ; then +# echo 'application/postscript ; /usr/bin/xdg-open %s' >> etc/mailcap +# echo >> etc/mailcap +#fi +#if ! grep -q '#text/html' etc/mailcap ; then +# echo '#text/html; /usr/bin/xdg-open %s ; copiousoutput' >> etc/mailcap +# echo >> etc/mailcap +#fi + +## END + |