Application: SAP EP-RUNTIME component Versions Affected: SAP EP-RUNTIME 7.5 Vendor URL: http://SAP.com Bugs: Denial of Service Sent: 22.04.2016 Reported: 23.04.2016 Vendor response: 23.04.2016 Date of Public Advisory: 12.07.2016 Reference: SAP Security Note 2315788 Author: Mathieu Geli (ERPScan) Description 1. ADVISORY INFORMATION Title: [ERPSCAN-16-029] SAP NetWeaver AS JAVA a deserialization of untrusted user value Advisory ID: [ERPSCAN-16-029] Risk: High Advisory URL: https://erpscan.com/advisories/erpscan-16-029-sap-netweaver-java-7-5-deserialization-untrusted-user-value-trustmanagementservlet/ Date published: 12.17.2016 Vendors contacted: SAP 2. VULNERABILITY INFORMATION Class: Denial of Service Impact: DoS Remotely Exploitable: Yes Locally Exploitable: No CVSS Information CVSS Base Score v3: 4.9 / 10 CVSS Base Vector: AV : Attack Vector (Related exploit range) Network (N) AC : Attack Complexity (Required attack complexity) Low (L) PR : Privileges Required (Level of privileges needed to exploit) High (H) UI : User Interaction (Required user participation) None (N) S : Scope (Change in scope due to impact caused to components beyond the vulnerable component) Unchanged (U) C : Impact to Confidentiality None (N) I : Impact to Integrity None (N) A : Impact to Availability High (H) 3. VULNERABILITY DESCRIPTION An attacker can use a special HTTP request in order to force a server to deserialize evil objects, which results in denial of service. 4. VULNERABLE PACKAGES SAP EP-RUNTIME component 5. SOLUTIONS AND WORKAROUNDS To correct this vulnerability, install SAP Security Note 2315788 6. AUTHOR Mathieu Geli (ERPScan) 7. TECHNICAL DESCRIPTION PoC Evil object in 'serial.cc3' as an attachment in this bug entry. It was generated with ysoserial framework, if the commons.collections jar was in the CLASSPATH we will have direct RCE. Now, we can only send DoS payloads that will trigger OutOfMemory exception on 7.5. Payload for that as attachment named 'serial.mem'. curl -v -XPOST --user 'user:password' http://172.16.30.29:50000/com.sap.portal.fpn.enterpriseservicesweb.mod/TrustManagementServlet --data-binary @serial.cc3 This request will trigger a series of exceptions in server's log. The DoS payload will render the server unstable for some minutes with following exception: Server process shutting down with exit code [666] memory allocation error [OutOfMemoryError] java.lang.OutOfMemoryError: Requested array size exceeds VM limit (failed to allocate 8589934576 bytes) (array length 2147483639) 8. REPORT TIMELINE Sent: 22.04.2016 Reported: 23.04.2016 Vendor response: 23.04.2016 Date of Public Advisory: 12.07.2016 9. REFERENCES https://erpscan.com/advisories/erpscan-16-029-sap-netweaver-java-7-5-deserialization-untrusted-user-value-trustmanagementservlet/ 10. ABOUT ERPScan Research ERPScan research team specializes in vulnerability research and analysis of critical enterprise applications. It was acknowledged multiple times by 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 of discovering new types of vulnerabilities (TOP 10 Web Hacking Techniques 2012) and of the "The Best Server-Side Bug" nomination at BlackHat 2013. ERPScan experts participated as speakers, presenters, and trainers at 60+ prime international security conferences in 25+ countries across the continents ( e.g. BlackHat, RSA, HITB) and conducted private trainings for several Fortune 2000 companies. ERPScan researchers carry out the EAS-SEC project that is focused on enterprise application security awareness by issuing annual SAP security researches. ERPScan experts were interviewed in specialized infosec resources and featured in major media worldwide. Among them there are Reuters, Yahoo, SC Magazine, The Register, CIO, PC World, DarkReading, Heise, Chinabyte, etc. Our team consists of highly-qualified researchers, specialized in various fields of cybersecurity (from web application to ICS/SCADA systems), gathering their experience to conduct the best SAP security research. 11. ABOUT ERPScan ERPScan is the most respected and credible Business Application Cybersecurity provider. Founded in 2010, the company operates globally and enables large Oil and Gas, Financial, Retail and other organizations to secure their mission-critical processes. Named as an aEmerging Vendora in Security by CRN, listed among aTOP 100 SAP Solution providersa 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. ERPScanas primary mission is to close the gap between technical and business security, and provide solutions for CISO's to evaluate and secure SAP and Oracle ERP systems and business-critical applications from both cyberattacks and internal fraud. As a rule, our clients are large enterprises, Fortune 2000 companies and MSPs, whose requirements are to actively monitor and manage security of vast SAP and Oracle landscapes on a global scale. We afollow the suna and have two hubs, located in Palo Alto and Amsterdam, to provide threat intelligence services, continuous support and to 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