[Full-disclosure] LutelWall <= 0.97 insecure temporary file creation

2005-06-06T00:00:00
ID SECURITYVULNS:DOC:8798
Type securityvulns
Reporter Securityvulns
Modified 2005-06-06T00:00:00

Description

LutelWall insecure temporary file creation

Vendor: http://firewall.lutel.pl/index.php Advisory: http://www.zataz.net/adviso/lutelwall-05222005.txt Vendor informed: yes Exploit available: yes Impact : medium Exploitation : low

The vulnerability is caused due to temporary file being created insecurely. This can be exploited via symlink attacks to create and overwrite arbitrary files with the privileges of the user running the affected script.

The exploitation require that the root try to update the software.

Versions:

LutelWall <= 0.97

Solution:

non solution yet.

Timeline:

Discovered : 2005-05-22 Vendor notified : 2005-05-22 Vendor response : none Vendor fix : no fix Disclosure : 2005-06-06

Technical details :

Vulnerable code :

Prefix of temporary firewall files

tmp='/tmp/lutelwall'

new_version_check () { # Check for new version of script

if [ "`wget -V 2>&1 >/dev/null`" ]; then message 3 "Warrning: Wget is required to check for updates." else new_ver=`wget -C off -O - -q -t 1 -T 3 -w 3 -U "\`uname -a 2>&1\`" http://firewall.lutel.pl/ver` if [ `echo $current_version | gawk '{ gsub("\\\.","") ; print 1$0 }'` -lt `echo $new_ver | gawk '{ gsub("\\\.","") ; print 1$0 }'` ]; then echo -e "\nThere is newer version of LutelWall (${new_ver})" echo -n " Changes since previous version:" echo `wget -C off -O $tmp-newfeat -q -t 1 -T 3 -w 3 http://firewall.lutel.pl/FEATURES-${new_ver}` cat $tmp-newfeat echo "Do you want to update [y/N]? " read -s -t 5 -n 1 ln if [ "$ln" = 'y' -o "$ln" = 'Y' ]; then wget -O $tmp-script -q -T 3 http://firewall.lutel.pl/lutelwall cat $tmp-script > $0 rm -rf $tmp-script echo "Your firewall is up to date, exiting after update!" exit else message 5 "Update aborted" fi else message 5 "LutelWall is up-to-date" fi; fi;

}

Related :

nothing related

Credits :

Eric Romang (eromang@zataz.net - ZATAZ Audit)


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