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Using EMET to defend against targeted attacks. Presented by Robert Hensing – Senior consultant – Microsoft Corporation Michael Mattes – senior consultant – Microsoft corporation. Who we are. Robert Hensing 15 year Microsoft employee TWC alum 5 year tour in MSRC Engineering – Defense team - PowerPoint PPT Presentation
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USING EMET TO DEFEND AGAINST TARGETED ATTACKSPRESENTED BY ROBERT HENSING – SENIOR CONSULTANT – MICROSOFT CORPORATIONMICHAEL MATTES – SENIOR CONSULTANT – MICROSOFT CORPORATION
WHO WE ARE
• Robert Hensing• 15 year Microsoft employee• TWC alum
• 5 year tour in MSRC Engineering – Defense team• Currently Developer Consultant in National Security Group practice
• Michael Mattes• XX year Microsoft employee• Infrastructure consultant in NSG etc.
TRUSTWORTHY COMPUTING - SECURITY CENTERS
Protecting Microsoft customers throughout the entire life cycle(in development, deployment and operations)
Microsoft Security
Engineering Center (MSEC)
Security Assurance
Security Science
SDL
Microsoft Malware Protection Center
(MMPC)ReleaseRelease
Product Life CycleProduct Life Cycle
Microsoft Security
Response Center(MSRC)Ecosystem
StrategyMSRC Ops
MSRC Engineering
ConceptionConception
Result: Attackers only have to find one vulnerability, and they get to use it for a really long time.
THE SOFTWARE VULNERABILITY ASYMMETRY PROBLEM
Defender must fix all vulnerabilities in all software – attacker wins by finding and exploiting just one vulnerability
Threats change over time – state-of-the-art in vulnerability finding and attack techniques changes over time
Patch deployment takes time – vendor must offset risks to stability & compatibility, customer waits for servicing cycle
EXPLOIT ECONOMICS
5
Gains per use
XOpportunities to use
Cost to acquire vulnerability
+Cost to weaponize
Attacker Return -=
Desired Result: Usable attacks will be rare and require significant engineering; working exploits will become scarce and valuable
EXPLOIT ECONOMICS
We can decrease Attacker Return if we are able to…Increase attacker investment required to find usable vulnerabilities• Remove entire classes of vulnerabilities where possible• Focus on automation to scale human efforts
Increase attacker investment required to write reliable exploits• Build mitigations that add brittleness• Make exploits impossible to write completely reliably
Decrease attacker’s opportunity to recover their investment• Shrink window of vulnerability• Fewer opportunities via artificial diversity• Enable rapid detection & suppression of exploit usage
INCREASE ATTACKER INVESTMENT REQUIRED TO FIND VULNERABILITIES
Exploit Economics Strategy – Step 1
7
EMBEDDING SECURITY INTO SOFTWARE AND CULTURE
Tactics for Vulnerability ReductionRemove entire classes of vulnerabilities • Security Tooling• Additional product features
Remove all currently findable vulnerabilities• Complete automation of tooling
• SDL tools, Threat Modeling tool• Fuzzing toolsets + ways to streamline & improve triage• Tool overlays to increase signal-to-noise and focus attention on the right code
• Verification & enforcement• Audit individual tool usage via process tools• Process tools required for SDL signoff - policy enforcement
Ongoing Process Improvements
PREVENT RELIABLE EXPLOITATION OF VULNERABILITIES
Exploit Economics Strategy – Step 2
EMBEDDING SECURITY INTO SOFTWARE AND CULTURE
Tactics to Frustrate ExploitsReduce the surface we have to defend• Attack surface reduction• Design additional product mitigations
Make remaining vulnerabilities difficult or impossible to exploit• Build mitigations that add exploit brittleness
Ongoing Process Improvements
DIGITAL COUNTERMEASURES
• Improve system survivability against exploitation of unknown vulnerabilities•Three goals:• Increase attacker requirements – e.g. must be
authenticated, local subnet only• Deterrent – no economically reliable exploit
exists•Mitigation – Break 100% reliable universal
exploits•Often must be combined together•Even when successful, the result is still impactful to the user 11
MITIGATION APPROACHES
• Utilize secrets such that guessing impairs exploit reliability• /GS: Protect stack buffers by checking random cookies
placed between them and control structures• Function Pointer Encoding
12
Utilize Knowledge Deficits
Artificial Diversity
Enforce Invariants
ASLR: Address Space Layout Randomization
Data Execute Protection (DEP)Heap & pool metadata checks SafeSEH / SEH Overwrite Protection (SEHOP)
MEMORY SAFETY MITIGATIONS ROADMAP
13
Stack
Heap / Pool
Executable Code
/GS 1.0 /GS 1.1
Heap 1.0
DEP ASLR DEP IE8
20072006200520042003
/GS 2.0
2008
/NXCOMPAT
Heap 2.0
HeapTerm
EH4 SEHOP /GS 3.0
DEP+ATL
Safe Unlinking
2009
DEP O14
2010 2011
SEHOPIE9
ENHANCED MITIGATION EXPERIENCE TOOLKIT (EMET) Offers security mitigations for most
software Old applications Third party software Line of business applications
Brings newer security mitigations to older platforms
Provides exclusive security mitigations to block current exploit techniques
EVOLUTION OF EMET MITIGATIONSMitigations in v1.0• Dynamic DEP• SEHOP• NULL Page protection
Mitigations in v2.0• Mandatory ASLR• EAT Access Filtering• Heap Spray Allocation
Mitigations in v3.0• 3 Protection Profiles• ADMX Files for Group
Policy Management• EMET Notifier (alerts
user when mitigations were enforced)
Mitigations in v3.5• Anti-ROP mitigations:
• Caller Checks• Exec Flow Simulation
• Stack Pivot Mitigation• Load Library Checks• Memory Protection Checks
MS12-037 – INTERNET EXPLORER CVE-2012-1875 (SAME ID)• 0-day vulnerability being used in limited targeted
attacks prior to bulletin release.• Vulnerability about as bad as it gets!• Remote Code Exec vulnerability in all versions of IE
(at the time) and exploitable via a web page• Fixed by MS12-037 - http://
technet.microsoft.com/en-us/security/bulletin/ms12-037• Standard mitigations in the bulletin were• Don’t open Office documents• Killbit the AX control in IE
EMET VS. MS12-037 - CVE-2012-1875 (SAME ID)
CALL TO ACTION
• Follow the Security Research and Defense bloghttp://blogs.technet.com/b/srd/ • Evaluate and Deploy EMET v3.5 or newer • Protect critical applications such as Internet Explorer, Firefox, Office,
Adobe Acrobat etc
• Monitor for EMET related events in the event log using System Center or other Enterprise monitoring software
DEPLOYMENT AND MANAGEMENT VIA GROUP POLICY