1. Securing Your Mobile Device: Emerging Trends
4/17/2017
Securing Your Mobile Device: Emerging Trends
Rob Coombs - Security Marketing Director

2. Agenda Introduction Four Compartment Security Model
Security Features of Modern Devices & CESG’s 12 Recommendations
Emerging Trends
Trusted Apps
FIDO – Moving beyond passwords
Summary

3. About ARM…. The World’s leading processor design company
Software development tools
Power Mgmt
Bluetooth
Cellular Modem
WiFi
SIM
GPS
Flash Controller
Touchscreen
Sensor Hub
Camera
Apps Processor
50 Billion ARM chips (>10B /year)
~ $1.2B Revenue/year
~3000 Employees
>95% Smartphone & Tablet market share
Physical IP – Design of the building blocks of the chip
Processor and Graphics IP – Design of the brain of the chip
So what is it we really do…
Well we don’t make the end devices you know and love…
<Click>
We don’t even make the semiconductor chips that go inside them…
We actually design some of the pieces of what goes inside those chips. We provide Intellectual Property in the form of the design of the processor or the graphics that power the chip. We also provide SW tools and support as well as other blocks within the chip.
And we don’t just do it for the main applications processor that runs your Android OS or apps, but we have a broad range of processors that can go into all of the other chips that make up your phone or other devices…

4. The Threat Environment
Increasing risks
Social engineering – trojans, phishing, APT
Malware
Physical loss or theft leading to risk to data – calendar, phonebook and
Improperly secured devices – no PIN lock
User intervention – jail breaking, unlocking
Mobile has become the enterprise security boundary
Need to design in the right system-wide security (not just more security)

5. PC Era Response to Threats: Pockets Full of Hardware
April 17, 2017
PC Era Response to Threats: Pockets Full of Hardware
TLS
DNSSEC
SSO
Call/text back
Challenge/response
CVC
To combat these issues, especially when deploying sensitive services over the internet, the PC security industry has tried its best to add layers of security on top of the operating and applications environment.
We have increasing use of trust concentration in technologies like SSO, and also of secure protocols like TLS and DNSSEC.
But these only go to the edges of applications., they don’t protect against targeted Trojans, Man-in-the-browser etc. So for real security applications like e-commerce and banking we are forced to add security through the use of extra hardware. We have out-of-band and multi-factor mechanisms like CVCs and phone-backs, we have one-time PIN devices and authorization tokens such as Mchip CAP readers.
[Animate]
And don’t forget each application or authority needs its own token tied to its own root of trust. This all gets very unwieldy and confusing for the user.

6. Applying Lessons to Modern Mobile Security
Hypervisor (with hardware support) separating large pieces of code
Small, certifiable Trusted Execution Environment inside Application processor isolated using ARM TrustZone® technology protecting against software attacks
Secure Element for tamper proof security
Hypervisor

7. TrustZone Based Trusted Execution Environment
Mobile devices with integrated HW security
Hardware root of trust
A basis for system integrity
Integrity through Trusted Boot
Secure peripheral access
Screen, keypad , fingerprint sensor etc.
Secure application execution
Technology called TrustZone®
Trust established outwards
With normal world apps
With internet/cloud apps

8. Castle Analogy Layers of defense Reducing attack surface
User Apps & Malware
Layers of defense
Reducing attack surface
Increasing isolation
Principle of least privilege
Most precious assets protected by multiple layers of security
User Apps
OS Hypervisor OS

9. Castle Analogy But… Modern OS/Framework is ~10GB + GBs of Apps
Crown Jewels
But…
Modern OS/Framework is ~10GB + GBs of Apps
So maybe we should think of a walled city & castle
Attacks happen
Everyone knows what the assets are and which room they are in
Where to put high value assets such as keys?
Thief entered here
& Stole keys!
Implementation details matter!

10. Castle Analogy with TrustZone Based TEE
TrustZone based TEE creates a second (much smaller security boundary) castle with only one door, carefully designed entry/exit & APIs
Keys only used in Secure World, Protected Crypto, Encrypted storage Secure execution Secure peripherals
Offers: Integrity (part of Trusted boot) Confidentiality
TrustZone TEE Castle is invisible to normal world
1-2MB
10-20 GB

11. Castle Analogy with TrustZone Based TEE
Secure World
Isolated Trusted Apps
Trusted OS e.g. Trustonic t-base300
Normal World
1-2MB
GlobalPlatform Client API SMC calls at SEL3
e.g. ARM Trusted Firmware
10-20 GB

12. Security Profiles SmartCards / HSMs Cost/Effort To Attack
TrustZone based TEE
Invasive HW Attacks
Well resourced and funded
Unlimited time, money & equipment.
Value to attacker
Non-invasive HW Attacks
Side channels (DEMA, DPA)
Physical access to device – JTAG, Bus Probing, IO Pins, etc.
Software Attacks
Malware & Viruses
Social engineering
Cost/Effort
to Secure

13. 4 Compartment Model – Hierarchy of Trust
Secure
Domain
Tamper Proof, Physically Isolated, EAL Certified
SecurCore™
SEE
Secure Element Smartcard
SIM & TPM
Trusted
Domain
TrustZone®
TEE
Secure Firmware Device Management Key Management
Trusted Applications executing from a Trusted Execution Environment
Protected
Domain
Hypervisor
HYP
Protected Video Path
BYOD
System Management
Virtual Machines and bus masters isolated by a Hypervisor
Rich
Domain
User Apps
Rich OS
Android or other OS
Privileged Supervisor Mode

14. Use Cases for Hierarchy of Trust Domains
Client Asset Protection
Content
Protection
Mobile
Payment
Enterprise
Government
Automotive
Server
Certification
Secure
UICC for smartphones
Secure Storage (CA)
Credit Card Payment
Wallet NFC
mPOS
(TEE +
SE)
Strong Authentication of user credentials
(eID)
GlobalPlatform
EMVCO
Trusted
MDM SIM Lock Trusted Storage
Trusted Boot
Trusted Apps
Trusted Storage (Keys)
DRM, CA
Trusted video playback path
Cloud Payment
Strong Authentication - Trusted UI Wallet
MDM BYOD Trusted UI Integrity
Trusted VPN
Trusted FOTA
MDM Trusted UI Key Store
Trusted Services (eTS)
Infotainment Integrity
Trusted boot
Integrity
Protected
Apps isolation
SW DRM
Isolation
BYOD
Dual Persona
Isolate Infotainment and CAN
VMs KVM, XEN…
Rich
SW Crypto
Web Remote
Payment (SSL)
SW BYOD
SW FOTA
FIPS 140.2

15. Web Payment Example: MasterPass

16. BYOD Trusted App Example: Good Technology
Trusted Apps run in a Trusted Execution Environment
TrustZone provides isolation from software attack
Ecosystem of Trusted App developers creating security-hardened apps and services
Good Technology Trusted Apps:
Password protection using secure touchscreen
Secure storage of crypto key
Result: Increased protection for business users
Open
Apps
Good Secure Apps
Good Technology Trusted Apps
TZ Driver
Secure OS
Android
ARM® Cortex™ Processor

17. Click and View – Downloadable DRM: Trustonic

18. Modern Practice
3 New whitepapers from Apple, Samsung and Microsoft give good insight into modern mobile security practice
Recommended reading for CIOs

19. CESG General Security Recommendations
Assured Data at Rest
Assured Data in Transit
Authentication
Secure Boot
Platform Integrity
Application white listing
Malicious Code Detection
Security Policy Enforcement
External Interface Protection
Device Update Policy
Event Collection
Incident Reponse

20. Encrypted Data at Rest and Data in Transit
Assured Data at Rest: Data at rest should be suitably encrypted
Typical ARM SoC has a crypto hardware engine to encrypt/decrypt files
Hardware Unique Key available only to Trusted OS, fused into silicon can be used to derive other keys
Key material can be kept on Secure World side or encrypted “wrapped” and stored as metadata
System Integrity as determined by Trusted Boot can be verified before the data is decrypted
Assured Data in Transit: IPSec VPN of “assured foundation grade” & configured appropriately
TrustZone based TEE can add strong 2 factor authentication for remote working

21. Authentication and Secure Boot
Authentication : based on User to Device, User to Service, Device to Service are used
Trusted peripherals are handled only by the secure world.
Protocols such as FIDO will simplify the silo nature of todays authentication market
Secure Boot: should not be modifiable by unauthorized entity & attempts should be detected
Device boots into Secure World and runs only cryptographically verified boot loaders
Device starts Trusted OS before main OS is started
Measurements of boot process can be made to test for tampering

22. Platform Integrity & Application White Listing
Platform Integrity: device protects key data despite compromise of an app/component
Sand boxing of Apps is routine (Separation of User and Kernel space)
Additional containers are placed around enterprise apps (possible use of HYP mode)
TEE assumes normal world is compromised
Apps within a container can be managed by Enterprise MDM
Only signed apps can run

23. Malicious Code Handling & Security Policy Enforcement
Malicious Code Handling: device can detect, isolate and defeat malicious code
Run time checking of OS can be done by TrustZone based TEE
Hierarchy of Trust limits exposure of assets
TrustZone based TEE assumes normal world is compromised
Security Policies can be enforced by the enterprise & cannot be overridden by user
MDM runs as a privileged trusted app in the TEE and cannot be deleted by user
MDM Containers

24. External Interface Protection & Device Update Policy
External Interface Protection: device can constrain ports and services exposed to untrusted networks
Inputs can be configured to be trusted or untrusted
Device Update Policy: Security updates can be issued by the enterprise & remotely validated
Secure World can be updated OTA e.g. management trusted app
May build on existing OEM capabilities e.g. configuration management, MDM policy management

25. Event Collection & Incident Response
Event Collection for enterprise analysis:
Device reports security events for audit/monitoring purposes
Tests and reports can be made from TrustZone based TEE and made available to MDM
Incident Response
Device Functionality needs to support Enterprise plan of action for a security incident
Remote wipe is a good candidate for a Trusted App (typically removing file encryption keys)

26. Agenda Introduction Four Compartment Security Model
Security Features of Modern Devices & CESG’s 12 Recommendations
Emerging Trends
Trusted Apps
FIDO – Moving beyond passwords
Summary

27. Trusted App Concept - Trustonic Example
Trusted Apps installed by OEM or
OTA (After market provisioning)
Access provided on demand as service providers need to use TEE enabled features

28. Connecting Trusted Device Supply with Service Provision

29. Trustonic Expands the Knox Framework

30. FIDO is about simpler and stronger authentication.
People use the same simple passwords (Analysis of 6m accounts showed that 10k common passwords would give access to 98.8% of the accounts)
1k passwords give access to 90% of the accounts see
10k passwords give access to 98.8% see
People reuse them
In 2007: People had 25 accounts and used 6.5 passwords (see Large Scale Study on Web Password habits)
73% of the users shared their online banking password with at least one non-financial site
Websites don’t protect them properly (LivingSocial – 50m, Evernote – 50m, Yahoo! Japan – 22m, Linkedin – 6.5m, Gawker – 1.3m, RockYou – 32m)
Adobe breach
Target breach
Yahoo! Japan – 22m in May 2013 see
LivingSocial – 50m in April 2013, see
Evernote – 50m in March 2013, see
LinkedIn - 6.5M in June 2012, see
Over 90% of the 6.5M hashed passwords stolen from LinkedIn were cracked within 6 days: 
eHarmony - 1.5M in June 2012, see
Gawker - 1.3M in December 2010, see
RockYou - 32M in December 2009, see
People forget them (More than 43% of users report that online transactions fail “Very Frequently” or “Frequently” due to authentication problems, Ponemon Study), Ever entered a 10 character password on a smartphone (with letters, digits and special characters)?
FIDO UAF supports arbitrary user verification methods (modalities).
Fast IDentity Online – a new industry alliance formed to develop technical standards that enable Internet Services to use Simpler Stronger Auth solutions
(a) Developing unencumbered Specifications that define interoperable mechanisms that supplant reliance on passwords
(b) Operating programs to help ensure industry adoption
(c) Submitting mature Specifications for formal standardization
© 2014 FIDO Alliance

31. FIDO User Experiences PASSWORDLESS EXPERIENCE (UAF standards)
Show a biometric
Transaction Detail
Done
SECOND FACTOR EXPERIENCE (U2F standards)
OK, let‘s get into the details of UAF.
There are 4 main functions supported by UAF.
Login & Password
Insert Dongle, Press button
Done

32. FIDO Functionality Discovery of authenticators on the client
Registration
Authentication
Transaction Confirmation
OK, let‘s get into the details of UAF.
There are 4 main functions supported by UAF.

33. How does FIDO UAF* work? FIDO Authenticators FIDO SERVER
Verification
[How does FIDO work?]
Map arbitrary User Authentication Methods to a small set of standard cryptographic authentication algorithms, e.g. asymmetric key challenge-response.
Note: all user authentication methods rely to some degree on at least one trusted component at the client side. With passwords and OTP the client environment has to make sure passwords/OTPs are not intercepted. PKI solution require a secure smart card. Biometric solutions rely on (at least) a trusted sensor.
If a session is to be authenticated, the user agent needs to be trusted as well.
In FIDO the mapping of the user authentication method to the standardized cryptographic authentication is done by the “FIDO Authenticator”.
*Universal Authentication Framework

34. FIDO - Universal Authentication Framework
User Side
Relying Party
Web Application
Plugin
SDK
UAF
Protocol
FIDO Client
FIDO UAF Server
Authenticator Abstraction
Attestation Manager
Ideal for TrustZone based TEE
Registration, Authentication & Transaction Confirmation
Crypto
Policy Rules
Authenticators
Authenticators
Authenticators
Private Keys
Authentication Keys
Attestation Key
Authentication Keys
Attestation Key
Public Keys

35. First FIDO Deployment already live…
Customers can use their finger to pay with PayPal from their new Samsung Galaxy S5 because the FIDO Ready™ software on the device securely communicates between the fingerprint sensor on their device and PayPal’s service in the cloud. The only information the device shares with PayPal is a unique cryptographic “public key” that allows PayPal to verify the identity of the customer without having to store any biometric information on PayPal’s servers.

36. Summary Mobile Security is built on hardware root of trust
Requires hardware, software and services to work together
Not all security is equal – consider ARM’s Hierarchy of Trust model
CESG recommendations and OEM security whitepapers useful for orientation
FIDO can help us move beyond passwords

37. References
Samsung Knox™ 2.0 Whitepaper
iOS Security
CESG End User Devices Security Guidance: General Recommendations
ARM Security Model