Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2015.2504
Endress+Hauser Fieldcare/CodeWrights HART Comm DTM XML
Injection Vulnerability
28 September 2015
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Endress+Hauser Fieldcare/CodeWrights HART Comm DTM
Publisher: ICS-CERT
Operating System: Network Appliance
Impact/Access: Execute Arbitrary Code/Commands -- Remote/Unauthenticated
Resolution: Patch/Upgrade
CVE Names: CVE-2015-6463
Original Bulletin:
https://ics-cert.us-cert.gov/advisories/ICSA-15-267-01
- --------------------------BEGIN INCLUDED TEXT--------------------
Advisory (ICSA-15-267-01)
Endress+Hauser Fieldcare/CodeWrights HART Comm DTM XML Injection
Vulnerability
Original release date: September 24, 2015
Legal Notice
All information products included in http://ics-cert.us-cert.gov are provided
"as is" for informational purposes only. The Department of Homeland Security
(DHS) does not provide any warranties of any kind regarding any information
contained within. DHS does not endorse any commercial product or service,
referenced in this product or otherwise. Further dissemination of this
product is governed by the Traffic Light Protocol (TLP) marking in the
header. For more information about TLP, see http://www.us-cert.gov/tlp/.
OVERVIEW
Alexander Bolshev of Digital Security has identified a vulnerability
within Endress+Hauser HART DTM software libraries. The vulnerability is in
handling of the HART longtag response field in Endress+Hauser's Fieldcare
and CodeWrights HART Comm DTM.
Endress+Hauser Process Solutions AG and CodeWrights have produced
new versions of the software that in combination mitigates the
vulnerability. Alexander Bolshev has tested the updated versions to validate
that it resolves the vulnerability.
This vulnerability could be exploited from an adjacent network receiving
HART DTM packets.
AFFECTED PRODUCTS
All HART DTM components relying on Fieldcare and a CodeWrights HART Comm
DTM are impacted. Individual components are not listed within this advisory
because of the extreme number of potentially impacted devices.
IMPACT
When a Device DTM component receives a HART packet response to Command
20 (longtag), it extracts the longtag from the packet. The string is
capable of storing an XML schema. The HART Comm DTM reads the XML schema
and attempts to retrieve XML schema or the document from the location
stored in the longtag. This leads to potential Server Side Request Forgery
(SSRF) attacks or XML External Entity attacks. This attack may cause the
disclosure of confidential data, denial of service, port scanning, and
other possible system impacts from the perspective of the machine where
the parser is located.
In an SSRF, the network connection will originate from the application
server internal IP, and an attacker will be able to use this connection to
bypass network controls. This could allow exposure of internal resources
that are not otherwise visible.
Impact to individual organizations depends on many factors that are unique
to each organization. NCCIC/ICS-CERT recommends that organizations evaluate
the impact of this vulnerability based on their operational environment,
architecture, and product implementation.
BACKGROUND
Endress+Hauser is an international company based in Germany and Switzerland,
with over 200 offices and production centers located worldwide.
CodeWrights GmbH is a German-based company that provides device integration
and management solutions. CodeWrights GmbH supplies components that are
used in DTMs of other vendors.
The Endress+Hauser Fieldcare manages the FDT/DTM Frame Application. The HART
Comm DTM is part of the FDT/DTM architecture used to provide communication
protocol information to the Frame Application. ICS-CERT has concluded these
devices are deployed across several sectors including Chemical, Commercial
Facilities, Critical Manufacturing, Energy, Food and Agriculture, Water
and Wastewater Systems, and others. ICS-CERT estimates that these DTMs
are used in products worldwide.
VULNERABILITY CHARACTERIZATION
VULNERABILITY OVERVIEW
XML CODE INJECTION[a]
XML schema is injected into the accepted response packet. When Comm DTM
reads longtag values from the Device DTM it attempts to parse the XML
schema potentially allowing for remote access and control.
CVE-2015-6463[b] has been assigned to this vulnerability. A
CVSS v3 base score of 8.3 and temporal score of 7.5 has been
assigned for each vulnerability; the CVSS vector string is
(AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L/E:P/RL:O/RC:C).[c]
VULNERABILITY DETAILS
EXPLOITABILITY
This vulnerability could be exploited from an adjacent network receiving
HART DTM packets.
EXISTENCE OF EXPLOIT
No known public exploits specifically target this vulnerability.
DIFFICULTY
An attacker with a low skill would be able to exploit this vulnerability.
MITIGATION
Endress+Hauser and CodeWrights have provided their own security advisories
and patches which can be found at:
Endress+Hauser: https://portal.endress.com/webdownload/FieldCareDownloadGui/
CodeWrights: http://www.codewrights.de/index.php/en/downloads/software
Asset owners using FieldCare or CodeWright HART Comm DTMs should update
their software to the newest version as soon as possible.
Some processes may require continual configuration changes. ICS-CERT
recommends asset owners maintain all software with the latest security
releases, limit connections outside the control system, and monitor approved
connections for suspicious traffic. ICS-CERT also recommends that asset
owners employ a least privilege practice and avoid unnecessary services
within their production environment.
ICS-CERT recommends that users take defensive measures to minimize the
risk of exploitation of this vulnerability. Specifically, users should:
Minimize network exposure for all control system devices and/or systems,
and ensure that they are not accessible from the Internet.
Locate control system networks and remote devices behind firewalls,
and isolate them from the business network.
When remote access is required, use secure methods, such as Virtual
Private Networks (VPNs), recognizing that VPNs may have vulnerabilities
and should be updated to the most current version available. Also
recognize that VPN is only as secure as the connected devices.
ICS-CERT reminds organizations to perform proper impact analysis and risk
assessment prior to deploying defensive measures.
ICS-CERT also provides a section for control systems
security recommended practices on the ICS-CERT web page at:
http://ics-cert.us-cert.gov/content/recommended-practices. Several
recommended practices are available for reading and download, including
Improving Industrial Control Systems Cybersecurity with Defense-in-Depth
Strategies.
Additional mitigation guidance and recommended practices are
publicly available in the ICS-CERT Technical Information Paper,
ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation
Strategies, that is available for download from the ICS-CERT web site
(http://ics-cert.us-cert.gov/).
Organizations observing any suspected malicious activity should follow their
established internal procedures and report their findings to ICS-CERT for
tracking and correlation against other incidents.
a.
CWE-91: XML Injection (aka Blind XPath Injection),
http://cwe.mitre.org/data/definitions/91.html, web site last accessed
September 24, 2015.
b.
NVD, http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-6463,
NIST uses this advisory to create the CVE web site report. This web
site will be active sometime after publication of this advisory.
c.
CVSS Calculator,
https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S...,
web site last accessed September 24, 2015.
Contact Information
For any questions related to this report, please contact ICS-CERT at:
Email: ics-cert@hq.dhs.gov
Toll Free: 1-877-776-7585
International Callers: (208) 526-0900
For industrial control systems security information and incident reporting:
http://ics-cert.us-cert.gov
ICS-CERT continuously strives to improve its products and services. You
can help by choosing one of the links below to provide feedback about
this product.
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to auscert@auscert.org.au
and we will forward your request to the appropriate person.
NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
http://www.auscert.org.au/render.html?cid=1980
===========================================================================
Australian Computer Emergency Response Team
The University of Queensland
Brisbane
Qld 4072
Internet Email: auscert@auscert.org.au
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for member emergencies only.
===========================================================================
-----BEGIN PGP SIGNATURE-----
Comment: http://www.auscert.org.au/render.html?it=1967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=UoKj
-----END PGP SIGNATURE-----