SAP NetWeaver AS ABAP 7.4 Directory Traversal
Posted on 19 November 2016
Application: SAP NetWeaver AS ABAP Versions Affected: SAP NetWeaver AS ABAP 7.4 Vendor URL: http://SAP.com Bugs: Directory traversal Sent: 22.04.2016 Reported: 23.04.2016 Vendor response: 23.04.2016 Date of Public Advisory: 09.08.2016 Reference: SAP Security Note 2312966 Author: Daria Prosochkina (ERPScan) Description 1. ADVISORY INFORMATION Title: [ERPSCAN-16-031] SAP NetWeaver AS ABAP a directory traversal using READ DATASET Advisory ID: [ERPSCAN-16-031] Risk: high Advisory URL: https://erpscan.com/advisories/erpscan-16-031-sap-netweaver-abap-directory-traversal-via-using-read-dataset/ Date published: 11.11.2016 Vendors contacted: SAP 2. VULNERABILITY INFORMATION Class: Directory traversal Impact: read file from system Remotely Exploitable: yes Locally Exploitable: yes CVSS Information CVSS Base Score v3: 4.3 / 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) Low (L) 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 Low (L) I : Impact to Integrity None (N) A : Impact to Availability None (N) 3. VULNERABILITY DESCRIPTION The code provides access to the file specified after the READ DATASET statement. The variable transmitted to the input of the statement is entered in it by user input. Thus, the user can access the files stored on the operating system. This vulnerability is called a Directory Traversal. The attack is possible if the application does not check the user data and does not delete special characters used for a directory traversal attack from the variable, in which the filename is passed. As a result, an attacker can read data from all files, to which the application has access. To discover this vulnerability, data flow analysis and other unique techniques are used. 4. VULNERABLE PACKAGES SAP_ABA 700 SAP_ABA 701 SAP_ABA 702 SAP_ABA 710 SAP_ABA 711 SAP_ABA 730 SAP_ABA 731 SAP_ABA 740 SAP_ABA 750 SAP_ABA 751 SAP_ABA 75A SAP_ABA 75B 5. SOLUTIONS AND WORKAROUNDS To correct this vulnerability, install SAP Security Note 2312966 6. AUTHOR Daria Prosochkina (ERPScan) 7. TECHNICAL DESCRIPTION Attacker can read any file from OS with use BUPA_BIP_FILE_IMPORT program. Filename used in statement READ DATASET (line 428) is entered in this statement by user input. User can pass to input arbitrary filepath, for example /etc/passwd. As a result of execution of the BUPA_BIP_FILE_IMPORT program, data from /etc/passwd will be written in P_FLEN variable in hex format. Vulnerable code 426. p_flen = 0. 427. DO. 428. READ DATASET p_ifilea INTO lw. 429.* Exit conditions for accessing in a loop 430. IF sy-subrc NE 0. EXIT. ENDIF. 431. APPEND lw TO p_itab . 432. 433. p_flen = p_flen + XSTRLEN( lw-d ) . 434. ENDDO. 8. REPORT TIMELINE Sent: 22.04.2016 Reported: 23.04.2016 Vendor response: 23.04.2016 Date of Public Advisory: 09.08.2016 9. REFERENCES https://erpscan.com/advisories/erpscan-16-031-sap-netweaver-abap-directory-traversal-via-using-read-dataset/ 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 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
