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Invest in security to secure investments Top 10 most interes.ng SAP vulnerabili.es and a9acks Alexander Polyakov CTO at ERPScan
Invest in security to secure investments
Top 10 most interes.ng SAP vulnerabili.es and a9acks
Alexander Polyakov CTO at ERPScan
About ERPScan
• The only 360-‐degree SAP Security solu8on -‐ ERPScan Security Monitoring Suite for SAP
• Leader by the number of acknowledgements from SAP ( 150+ ) • 60+ presenta.ons key security conferences worldwide • 25 Awards and nomina.ons • Research team -‐ 20 experts with experience in different areas
of security • Headquarters in Palo Alto (US) and Amsterdam (EU)
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What is SAP ?
Shut up And Pay
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Really
• The most popular business applica8on • More than 120000 customers • 74% of Forbes 500
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Agenda
• Intro • SAP security history • SAP on the Internet • Top 10 latest interes8ng aPacks • DEMOs • Conclusion
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3 areas of SAP Security
2010 Applica3on pla4orm security
Prevents unauthorized access both insiders and remote a3ackers
Solu8on: Vulnerability Assessment and Monitoring
2008
ABAP Code security Prevents a3acks or mistakes made by developers Solu8on: Code audit
2002
Business logic security (SOD) Prevents a3acks or mistakes made Solu8on: GRC
Talks about SAP security
0
5
10
15
20
25
30
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2006 2007 2008 2009 2010 2011 2012
Most popular: • BlackHat • HITB • Troopers • RSA • Source • DeepSec • etc.
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SAP Security notes
0
100
200
300
400
500
600
700
800
900
2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012
By April 26, 2012, a total of 2026 notes
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SAP vulnerabili.es by type
0 50 100 150 200 250 300 350
12 -‐SQL Inj
11 -‐ BOF
10 -‐ Denial of service
9 -‐ Remote Code Execu8on
8 -‐ Verb tampering
7 -‐ Code injec8on vulnerability
6 -‐ Hard-‐coded creden8als
5 -‐ Unauthorized usage of applica8on
4 -‐ Informa8on Disclosure
3 -‐ Missing Auth check
2 -‐ XSS/Unauthorised modifica8on of stored
1 -‐ Directory Traversal
Stats from : • 1Q 2012 • 1Q 2010 • 4Q 2009
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SAP on the Internet
• We have collected data about SAP systems in the WEB • Have various stats by countries, applica8ons, versions • Informa8on from Google, Shodan, Nmap scan
MYTH: SAP systems a9acks available only for insiders
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SAP on the Internet
About 5000 systems including Dispatcher, Message server, SapHostcontrol, Web-‐ services
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SAP on the Internet
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Top 10 vulnerabili.es 2011-‐2012
1. Authen8ca8on Bypass via Verb tampering 2. Authen8ca8on Bypass via the Invoker servlet 3. Buffer overflow in ABAP Kernel 4. Code execu8on via TH_GREP 5. MMC read SESSIONID 6. Remote portscan 7. Encryp8on in SAPGUI 8. BAPI XSS/SMBRELAY 9. XML Blowup DOS 10. GUI Scrip8ng DOS
NNw NNw
NNw
NNw
NNw
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10 – GUI-‐Scrip.ng DOS: Descrip.on
• SAP users can run scripts which automate their user func8ons • A script has the same rights in SAP as the user who launched it • Security message which is shown to user can be turned off in
the registry • Almost any user can use SAP Messages (SM02 transac8on) • It is possible to run DOS aPack on any user using a simple script
New
Author: Dmitry Chastukhin (ERPScan)
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10 – GUI-‐scrip.ng: Other a9acks
Script can be uploaded using:
– SAPGUI Ac8veX vulnerability – Teensy USB flash – Any other method of client exploita8on
Other a9acks like changing banking accounts in LFBK also possible
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10 – GUI-‐scrip.ng: Business risks
Sabotage – High
Ease of exploita.on – Medium
Espionage – No
Fraud – No
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10 – GUI-‐scrip.ng: Preven.on
• SAP GUI Scrip8ng Security Guide • sapgui/user_scrip8ng = FALSE • Block registry modifica8on on worksta8ons
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9 – XML Blowup DOS: Descrip.on
• WEBRFC interface can be used to run RFC func8ons • By default any user can have access • Even without S_RFC auth • SAP NetWeaver is vulnerable to malformed XML packets • It is possible to run DOS aPack on server using simple script • It is possible to run over the Internet!
New
Author: Alexey Tyurin (ERPScan)
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9 – XML Blowup DOS: Demo
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9 – XML Blowup DOS: Business risks
Ease of exploita.on – Medium
Espionage – No
Fraud – No
Sabotage – Cri.cal
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9 – XML Blowup DOS: Preven.on
• Disable WEBRFC • Prevent unauthorized access to WEBRFC using S_ICF • Install SAP notes 1543318 and 1469549
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8 – BAPI script injec.on/hash stealing : Descrip.on
• SAP BAPI transac8on fails to properly sani8ze input
• Possible to inject JavaScript code or link to a fake SMB server • SAP GUI clients use Windows so their creden8als will be
transferred to aPackers host.
Author: Dmitry Chastukhin (ERPScan)
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8 – BAPI script injec.on/hash stealing: Demo
New
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8 – BAPI script injec.on/hash stealing: Business risks
Ease of exploita.on – Low
Sabotage – High
Espionage – High
Fraud – High
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7 – SAP GUI bad encryp.on: Descrip.on
• SAP FrontEnd can save encrypted passwords in shortcuts • Shortcuts stored in .sap file • This password uses byte-‐XOR algorithm with “secret” key • Key has the same value for every installa8on of SAP GUI • Any password can be decrypted in 1 second
Author: Alexey Sintsov (ERPScan)
New
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7 – SAP GUI bad encryp.on: Business risks
Sabotage – Medium
Fraud – High
Espionage – High
Ease of exploita.on – Medium
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7 – SAP GUI bad encryp.on: Preven.on
• Disable password storage in GUI
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6 – Remote port scan via JSP: Descrip.on
• It is possible to scan internal network from the Internet • Authen.ca.on is not required • SAP NetWeaver J2EE engine is vulnerable
• /ipcpricing/ui/BufferOverview.jsp? • server=172.16.0.13 • & port=31337 • & password= • & dispatcher= • & targetClient= • & view=
Author: Alexander Polyakov (ERPScan)
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6 – Remote port scan via JSP: Demo
Port closed
HTTP port
SAP port
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6 – Remote port scan via JSP: Business risks
Espionage – Medium
Fraud – No
Ease of exploita.on – High
Sabotage – Low
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6 – Remote port scan via JSP: Preven.on
• Install SAP notes: 1548548, 1545883, 1503856, 948851, 1545883
• Disable unnecessary applica8ons
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5 – MMC JSESSIONID stealing: Descrip.on
• Remote management of SAP Platorm • By default, many commands go without auth • Exploits implemented in Metasploit (by ChrisJohnRiley) • Most of the bugs are informa8on disclosure • It is possible to find informa8on about JSESSIONID • Only if trace is ON
Can be authen.cated as an exis.ng user remotely
1) Original bug by ChrisJohnRiley 2) JSESSIONID by Alexey Sintsov and
Alexey Tyurin (ERPScan)
New
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5 – MMC JSESSIONID stealing: Business risks
Espionage – Cri.cal
Sabotage – Medium
Fraud – High
Ease of exploita.on – Medium
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5 – MMC JSESSIONID stealing: Preven.on
• The JSESSIONID by default will not be logged in log file • Don’t use TRACE_LEVEL = 3 on produc8on systems or delete traces
aver use • Other info hPp://help.sap.com/saphelp_nwpi71/helpdata/en/
d6/49543b1e49bc1fe10000000a114084/frameset.htm
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4 – Remote command execu.on in TH_GREP: Descrip.on
• RCE vulnerability in RFC module TH_GREP • Found by Joris van de Vis • SAP was not properly patched (1433101) • We have discovered that the patch can be bypassed in Windows
Original bug by Joris van de Vis (erp-‐sec) Bypass by Alexey Tyurin (ERPScan)
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4 – RCE in TH_GREP: Details
elseif opsys = 'Windows NT'. concatenate '/c:"' string '"' filename into grep_params in character mode. else. /*if linux*/ /* 185 */ replace all occurrences of '''' in local_string with '''"''"'''.
/* 186 */ concatenate '''' local_string '''' filename into grep_params /* 187*/ in character mode. /* 188*/ endif.
/* 188*/
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4 – RCE in TH_GREP: Demo #1
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4 -‐ RCE in TH_GREP: More details
4 ways to execute vulnerable program • Using transac8on "Se37“ • Using transac8on “SM51“ (thanks to Felix Granados) • Using remote RFC call "TH_GREP" • Using SOAP RFC call "TH_GREP" via web
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4 – RCE in TH_GREP: Demo #2
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4 – RCE in TH_GREP: Business risks
Sabotage – Medium
Fraud – High
Espionage – High
Ease of exploita.on – medium
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4 – RFC in TH_GREP: Preven.on
• Install SAP notes 1580017, 1433101 • Prevent access to cri8cal transac8ons and RFC func8ons • Check the ABAP code of your Z-‐transac8ons for similar vulnerabili8es
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3 -‐ ABAP Kernel BOF: Descrip.on
• Presented by Andreas Wiegenstein at BlackHat EU 2011 • Buffer overflow in SAP kernel func8on C_SAPGPARAM • When NAME field is more than 108 chars • Can be exploited by calling an FM which uses C_SAPGPARAM • Example of report – RSPO_R_SAPGPARAM
Author: (VirtualForge)
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3 – ABAP Kernel BOF: Business risks
Espionage – Cri.cal
Ease of exploita.on – Medium
Fraud – Cri.cal
Sabotage – Cri.cal
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3 – ABAP Kernel BOF: Preven.on
• Install SAP notes: -‐ 1493516 – Correc8ng buffer overflow in ABAP system call -‐ 1487330 – Poten8al remote code execu8on in SAP Kernel
• Prevent access to cri8cal transac8ons and RFC func8ons • Check the ABAP code of your Z-‐transac8ons for cri8cal calls
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2 – Invoker Servlet: Descrip.on
• Rapidly calls servlets by their class name
• Published by SAP in their security guides
• Possible to call any servlet from the applica8on
• Even if it is not declared in WEB.XML
Can be used for auth bypass
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2 -‐ Invoker Servlet: Details
<servlet> ! <servlet-name>CriticalAction</servlet-name> ! <servlet-class>com.sap.admin.Critical.Action</servlet-class> !</servlet>!<servlet-mapping> ! <servlet-name>CriticalAction</</servlet-name> ! <url-pattern>/admin/critical</url-pattern> ! </servlet-mapping!<security-constraint>!<web-resource-collection>!<web-resource-name>Restrictedaccess</web-resource-name>!<url-pattern>/admin/*</url-pattern>!<http-method>GET</http-method>!</web-resource-collection>!<auth-constraint> !<role-name>admin</role-name> !</auth-constraint>!</security-constraint>!
Author: Dmitry Chastukhin (ERPScan)
What if we call /servlet/com.sap.admin.Cri.cal.Ac.on
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2 – Invoker servlet: Business risks
Ease of use – Very easy!
Espionage – High
Sabotage – High
Fraud – High
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2 -‐ Invoker servlet: Preven.on
• Update to the latest patch 1467771, 1445998 • “EnableInvokerServletGlobally” property of the servlet_jsp must be “false” If you can’t install patches for some reason, you can check all WEB.XML files using ERPScan web.xml scanner manually.
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1 – VERB Tampering
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1st Place – Verb Tampering
<security-constraint>!<web-resource-collection>!<web-resource-name>Restrictedaccess</web-resource-name>!<url-pattern>/admin/*</url-pattern>!<http-method>GET</http-method>!</web-resource-collection>! !<auth-constraint> !<role-name>admin</role-name> !</auth-constraint>!</security-constraint>!!
What if we use HEAD instead of GET ?
Author: Alexander Polyakov (ERPScan)
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1 – Verb tampering: Details
Remotely without authen.ca.on!
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• CTC – Secret interface for managing J2EE engine • Can be accessed remotely • Can run user management ac8ons:
– Add users – Add to groups – Run OS commands – Start/Stop J2EE
1 – Verb tampering: Demo
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1 – Verb tampering: More details
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If patched, can be bypassed by the Invoker servlet!
1 – Verb tampering: Business risks
Espionage – Cri.cal
Sabotage – Cri.cal
Fraud – Cri.cal
Ease of use – Very easy!
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1st Place – Verb tampering: Preven.on
Preven8on: • Install SAP notes 1503579,1616259 • Install other SAP notes about Verb Tampering (about 18) • Scan applica8ons using ERPScan WEB.XML check tool or manually • Secure WEB.XML by dele8ng all <hPp-‐method> • Disable the applica8ons that are not necessary
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Conclusion
It is possible to be protected from almost all those kinds of issues and we are working hard with SAP to make it secure
SAP Guides
It’s all in your hands
Regular Security assessments
ABAP Code review
Monitoring technical security
Segrega.on of Du.es
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Future work
Many of the researched things cannot be disclosed now because of our good relaGonship with SAP Security Response Team, whom I would like to thank for cooperaGon. However, if you want to see new demos and 0-‐days, follow us at @erpscan and a3end the future presentaGons:
• PHDays in May (Moscow) • Just4Mee8ng in July (Portugal) • BlackHat USA in July (Las Vegas)
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Greetz to our crew who helped: Dmitriy Evdokimov, Alexey Sintsov, Alexey Tyurin, Pavel Kuzmin, Evgeniy Neelov.
web: www.erpscan.com e-‐mail: [email protected] [email protected] TwiPer: @erpscan @sh2kerr
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