OS Command Injection & Reflected Cross Site Scripting In OpenEMR

Title

OS Command Injection & Reflected Cross Site Scripting

Product

OpenEMR

Vulnerable Version

5.0.0

Fixed Version

5.0.0 Patch 2 or higher

CVE Number

-

Impact

critical

Found

03.03.2017

By

Wan Ikram, Fikri Fadzil, Jasveer Singh (Office Kuala Lumpur) | SEC Consult Vulnerability Lab

The “OpenEMR” software is vulnerable to OS command injection which allows an attacker to compromise the server hosting the affected software. Furthermore, reflected cross site scripting vulnerabilities exist as well.

Vendor Description

“OpenEMR is the most popular open source electronic health records and medical practice management solution. ONC certified with international usage, OpenEMR’s goal is a superior alternative to its proprietary counterparts.”

Source: http://www.open-emr.org/

Business Recommendation

By exploiting the vulnerability documented in this advisory, an attacker can fully compromise the web server which has OpenEMR installed. Potentially sensitive health care and medical data might get exposed through this attack.

SEC Consult recommends not to attach OpenEMR to the network until a thorough security review has been performed by security professionals and all identified issues have been resolved. It is assumed that OpenEMR is affected by further critical security issues.

Vulnerability Overview/ Description

1. OS Command Injection

Any OS commands can be injected by an authenticated attacker with any role. This is a serious vulnerability as the chance for the system to be fully compromised is very high.

2. Reflected Cross Site Scripting

This vulnerability allows an attacker to inject malicious client side scripting which will be executed in the browser of users if they visit the manipulated site. There are different issues affecting various components. The flash component has not been fixed yet as OpenEMR is looking for a replacement component.

Proof Of Concept

1. OS Command Injection

Below is the detail of a HTTP request that needs to be sent to execute arbitrary OS commands through “fax_dispatch.php”.

URL : http:// $DOMAIN/interface/fax/fax_dispatch.php?scan=x
METHOD : POST
PAYLOAD : form_save=1&form_cb_copy=1&form_cb_copy_type=1&form_images[]=x&form_
filename='||<os-commands-here>||'&form_pid=1

 

2. Reflected Cross Site Scripting

The following URL parameters have been identified to be vulnerable against reflected cross site scripting:

The following payload shows a simple alert message box:
a)
 

URL : http:// $DOMAIN/library/openflashchart/open-flash-chart.swf
METHOD : GET
PAYLOAD : [PoC removed as no fix is available]

b)

URL : http:// $DOMAIN/library/custom_template/ckeditor/_samples/assets/_posteddata.php
METHOD : POST
PAYLOAD : <script>alert('xss');</script>=SENDF

Vulnerable / Tested Versions

OpenEMR version 5.0.0 has been tested. This version was the latest at the time the security vulnerability was discovered.

Vendor Contact Timeline

2017-03-08: Contacting vendor through email.
2017-03-08: Vendor replied with his public key. Advisory sent through secure channel.
2017-03-17: Asked for a status update from the vendor.
2017-03-17: Vendor confirms the vulnerabilities and working on the fixes.
2017-03-31: Asked for a status update from the vendor.
2017-03-31: Vendor informed that they have fixed OS Command Injection and are currently working on fixes for Reflected Cross Site Scripting.
2017-04-16: Vendor publishes Patch 2 which fixes command injection & XSS issue 2b)
2017-04-25: Vendor requesting extension for deadline of 32 days from the latest possible release date.
2017-05-25: Asked for a status update from the vendor.
2017-05-29: Vendor informed that they are working on the fixes.
2017-06-06: Asked for a status update from the vendor.
2017-06-12: Vendor informed that they added solution into the development codebase.
2017-07-05: Asked for a status update from the vendor.
2017-07-10: Vendor informed patch is delayed due to another critical bug fixes.
2017-08-17: Asked for a status update from the vendor. No reply.
2017-08-24: Asked for a status update from the vendor.
2017-08-29: Vendor informed patch will be out soon.
2017-08-30: Asked vendor for specific release date for patch. No reply.
2017-09-08: Asked for a status update from the vendor. No reply.
2017-09-14: Asked for a status update from the vendor.
2017-09-18: Vendor informed that they are testing their patch. No estimation yet on the patch release date.
2017-10-17: Asked for a status update from the vendor. No reply.
2017-10-30: Asked for a status update from the vendor.
2017-10-31: Vendor informed that the patch will be released as soon as possible.
2017-11-15: Asked for a status update from the vendor.
2017-11-21: Vendor informed that they are working on other vulnerabilities.
2017-11-30: Public release of SEC Consult advisory.
2017-12-04: Vendor publishes Patch 7 to fix XSS issue 2a, updated advisory.

Solution

The vendor has fixed the code execution issue and XSS 2b) in GIT in March 2017:
https://github.com/openemr/openemr/commit/ee0945a30dbb17ceee82b9b553d7dcb177710ca8#diff-1fdae02fadfcbc6147352cdc7c63279a
The fix has been incorporated in 5.0.0 Patch 2 or higher. The XSS example 2a (flash) is fixed in Patch 7.

Because of critical security issues (CVE-2017-16540) of other security researchers it is highly recommended to upgrade to at least version 5.0.0 Patch 7 immediately.

http://www.open-emr.org/wiki/index.php/OpenEMR_Patches

Workaround

None

Advisory URL

https://www.sec-consult.com/en/vulnerability-lab/advisories/index.html

 

EOF Jasveer Singh / @2017

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