Monday, March 28, 2011

Reverse Engineering Through Inline Hooking

Reverse Engineering techniques are generally divided into two broad categories:
1. Static Analysis
2. Dynamic Analysis

Static Analysis
-Techniques which do not involve running the code
-Disassembly, file structure analysis, strings, etc.

Dynamic Analysis
-Techniques which involve running the code
-Behavioral analysis

Approaches to Dynamic analysis involve:
-Network Monitoring
      Isolated Physical Networks
      Virtual Networks
-Hardware Emulation
      Norman Sandbox, etc.
-Kernel-Level Monitoring (SSDT hooks)
      Sysinternal Process Monitor
-Debuggers

Kernel-Level Monitoring


Advantages
      Captures every system call
      Can’t be avoided from userland
Disadvantages
      Only captures functions implemented as system calls
      Not every important function call in the Win32 API is implemented as a system call
      Tools don’t differentiate between process housekeeping and calls from usercode
      Calls to internal DLL’s cannot be observed

Process Monitoring via Debugging
Advantages
      Debugger can trap any function call, not just system calls
      Trapped calls are more likely to be highly relevant to the program’s operation
Disadvantages
      Have to act as a debugger
      Susceptible to countless anti-debugging techniques

Inline Hooks
Advantages
      Can trap any function call, not just system calls
      Trapped calls are more likely to be highly relevant to the program’s operation
      Not operating as a debugger
      No device driver required
Disadvantages
      Hard to implement
Implementing Inline Hooks
1. Find a function of interest
2. Disassemble the beginning of the function
3. If possible, overwrite the beginning bytes of the function with a jump or call instruction
4. Implement a handler for the hooked function

What to do with hooked functions?
Observe and Report
      Collect data about the current function call by gathering data from stack and report to console
      Execute any instructions overwritten from the hook
      Jump back to the next instruction in the hooked function
Intercept and Emulate
      Perform a specified action instead of calling the intended function

Running your own Sandbox
-Trap gethostbyname() to always return a fixed IP address.
-A pseudo-handle interface to allow fake reads and writes to files and netwok sockets. Trap connect() to connection to a pseudo-socket. CreateFile(), ReadFile(), WriteFile(), etc.

API Thief Tool (by mandiant.com)
-Launches target process in a suspended state
-Injects a DLL into the process.
-The Injected DLL hooks all Win32 API functions before the target process is resumed
-API Call monitoring can be used simply with a process monitor-style console
-Embedded python can be used to write custom handlers for specific hooked functions

Dissecting Malicious Office Documents


In the past, malware was only appearing as an executable file but this threat has changed its landscape to skew through the application data files which includes, pdf, doc, xls, etc. In order to combat this threat, MalOffice has introduced a combination of both "static" and "dynamic" analysis techniques to inspect the application data files. The static analysis uses general and filetype-dependable scanning while the dynamic analysis uses the approach of CWSandbox and other test analysis techniques.

Static Analyzers
General:
-AV Scanner
-PE-Detector

Specialized:
-Detect embedded javascript in PDF document
-Heuristics for malicious javascript
-Detect shellcode in Office documents

PDFScanner
Specialized scanner for PDF files
-Decompose PDF stream into objects (pdftoolkit)
-Detect javascript objects
-Use heuristics to detect malicious javascript
-Extract Variable names
-Find code obfuscation
-Usage of known vulnerable functions

OfficeMalScanner
Specialized scanner for MS Word files
-Uses OfficeMalScanner, by Frank Boldewin (http://www.reconstructer.org)
-Forensic tool for Office documents
-Scans for shellcode pattern
-Dumps OLE structures and VB-macros
-Generates a malicious index value
Limitations
Static analyis can be circumvented by attacker
-different kinds of obfuscation are possible
-general drawbacks of static malware analysis
-exploit might trigger only on certain events
-Exploit might require specific version

Dynamic Analyzers

CWSandbox
-Tool for automated behavior analysis
-PE-executables or arbitrary data files
-Creates XML analysis report: operations executed by the monitored processes
-Filesystem, registry, network, user management,services, protected storage, etc
-Each file type has associated host application e.g. Acrobat Reader, Foxit Reader, MS Word, etc
-Some exploits only trigger in specific app versions e.g. Acrobat Reader 8.0, 8.1.0, 8.1.1, 9.0
-Task: decide from analysis report, if executed data file is malicious based on "Policies"
-consist of white and blacklisted operations
-created in a semi-automated way
-One policy per host application version
-What operations are usually perfomed when running this application with a (benign) data file?

Static Analysis Result (suspicious points)

Dynamic Analysis Result (malicious points)

Other Tools
SPARSE - focus only on Word documents
OfficeCat - static scanner for office documents
OfficeMalScanner - MS office forensic tool
Wepawet - powerful tool to analyze PDF and Flash files

Insights of the CyberCrime World


Malware Trends
-High complexity of technology introduces higher number of fault (Hardware, Software)
-Proof of Concept, Exploit Codes, Vulnerabilities (Finding exploits in order to misuse them, making money!)
-Today's Malware (Organized in botnets, uses human vulnerabilities)
-Botnets (Money making operation by selling stolen credentials, renting out botnet services like DDoS, Adware installations, etc)
 
Anti-Malware Solutions
The decision about the detection of malware (adware, spyware, trojan, etc) can be troublesome. It can be difficult to give a reason why any software is malicious, unwanted or not useful. However, implementing detection mechanism can be rather easy but there is an exception to this rule. Additionally, there is always a need for the cooperation between AV companies to avoid ambiguous decisions. This can be established by introducing standards and best practices such as AVPD, ASC, AMTSO, etc.

Detection vs Decision in Terms of Malware
Malware Distribution Channels
Trojan or Normal Application?
Trojan
-Uncompromising infection
-Make use of exploits
-Unattended, unsolicited installation
-Perform stealth activities
-Invasiveness
-Impact on system stability, security and integrity
-Obfuscated data
-Detection evasion mechanism

Normal Application
-The application itself isn't causing any harm
-EULA, the installation take place with user's consent
-The vendors disclaim involvement with the distribution channels

Vendors doesn't want their application to be detected
 
 
Final Outlook of the Malware
Legal and Problematic Issues
-Applications developed by well-established companies roll out with different affiliate distribution
model. Now, typically with botnet era?
-Mutual customers: those who want to use software and be protected at the same time.
-Other customers: those who never agree to install anything without their trustful consent.
-Uncontrolled open affiliate distribution model is unfeasible.
-Direct sponsorship for cybercrime activities.
-Once detected, these criminal groups are ready to fight even for the price of lawsuit.

Over the Past 4-years (according to Eset AV Press)
-20+ cases where the legal department has been involved
-Over 1150 hours and 530 employee interactions
-2006: 16 hours/month, 6 total interactions
-2009: 46 hours/month, 21 total interactions

Defeating OS Fingerprinting Using IpMorph


IpMorph is an Open Source project used to disguise OS-detection process performed using various techniques, such as, banner grabbing, ICMP replies, ISN profile, TCP headers, timeouts and other similar trends. These techniques are usually available in number of tools like Nmap, Xprobe2, SinFP, Ring2, p0f, Ettercap, etc.

Active Stack Fingerprinting











Passive Stack Fingerprinting












How IpMorph Works













Spoofing States
Filtering
– Stealth patch : Unmaintained as of 2002, GNU/Linux kernel 2.2-2.4
– Blackhole : FreeBSD, kernel options
– IPlog : Unmaintained as of 2001, *BSD
– Packet filter : OpenBSD
Host TCP/IP stack tweaking
– Ip Personality
– Fingerprint opt
– Fingerprint scrubber
– OSfuscate
Host TCP/IP stack replacement (proxy behaviour)
– Honeyd
– Packet purgatory / Morph
Integrated Tools
–IpMorph (Core)
–IpMorph Controller
–IpMorph Personality Manager
–IpView (IpMorph GUI)
Portability
–GNU/Linux
–BSD, Mac OS

IpMorph General Architecture

Breaking Into SharePoint Portal


Windows SharePoint Services (WSS)
- Base technology
- Free (with Windows Server)
- Consists of an ASP.NET web site and ISAPI filter

Microsoft Office SharePoint Server (MOSS)
- Built on top of WSS
- Not free
- Supports collaboration on MS Office documents

Security Aware?
- Gartner predicts SharePoint will replace network file shares
- Default security model: all site users have read access to all documents
- Big target – single repository for sensitive corporate data – salaries, phone numbers, customer lists,  passwords, strategic plans, etc.

Hacking the SharePoint ISAPI Registry
A potential EoP, but not interesting:
- Requires Terminal Services to be enabled with “NT4 compat mode”
- In that scenario, several Windows components have the same bug
- See “Web Server Extensions”, referenced in HKLM
- Check out usage of “Terminal Server User” SID throughout Windows

Hacking SharePoint with Google
- Thousands of public, internet-facing SharePoint sites have been created
- Use Google to identify configuration mistakes
- More info: http://tinyurl.com/4dccn9

Hacking SharePoint with NMap
- SharePoint servers have a distinctive network port signature
- Depends on firewall config, of course
- More info: http://tinyurl.com/3oykwp

Hacking SharePoint with RegEx
SharePoint RegEx Search
- http://www.codeplex.com/MossRegExSearch
- See blog post – http://tinyurl.com/4s49p3
- Avoid limitations of built-in SharePoint search (i.e., SQL ‘LIKE’ and ‘CONTAINS’ keywords)
- Instead, harness the power of regular expressions!
- Search for: strong passwords, credit card info, phone numbers, SSNs, etc.

Using DAVIX For Security Visualization (revised)


Information visualization
-Visualize large collections of abstract data

Scientific visualization
-Representation of data with geometric structure



Visualization Concept
-Analyzing floods of data in tabular or textual form is tedious
-Humans must sequentially scan such data
-Visualization exploits the human's visual perceptive capabilities and parallel processing Size, Shape, Distance, and Color
-Easy to spot patterns and irregularities

Data types supported
-Ordinal
Has a sequence e.g. day of week
-Nominal
Has no sequence e.g. types of fishes
-Quantitative
Can be measured e.g. length, time, weight, temperature, speed

Visualization Effectiveness
-Each data type has its most effective way of visualization


Information Visualization Process



DAVIX Linux Distribution (http://davix.secviz.org/)
-Provide the audience with a workable and integrated tools set
-Enable them to immediately start with security visualization
-Motivate them to contribute to the security visualization community

Tools Available
Capture
-Network Tools (Argus, Snort, Wireshark)
-Logging (syslog-ng)
-Fetching Data (wget, ftp, scp)

Processing
-Shell Tools (awk, grep, sed)
-Visualization Preprocessing (AfterGlow, LGL)
-Extraction (Chaosreader)
-Data Enrichment (geoiplookup, whois, gwhois)

Visualization
-Network Traffic (EtherApe, InetVis, tnv)
-Generic (AfterGlow, Cytoscape, Graphviz, LGL Viewer, Mondrian, R Project, Treemap)

Interface Transport
-Each visualization tool has its own file format interfaces
-Data must be converted to match the import interfaces
-These adapters are mostly self-written snippets of code

Important Note:
All the images presented in this post are intellectual property of the copyright owner (www.secviz.org)

Tuesday, March 1, 2011

Defending BGP MITM (Man-In-The-Middle) Attacks

Every organization owes its Internet connectivity to one protocol: BGP4. There are no alternatives. BGP4 has longstanding vulnerabilities that cannot be fixed, and can only be monitored carefully.

Two key points:
1. Everyone who connects to the Internet is currently exposed to various routing risks: downtime, hijacking and now even wholesale traffic interception.
2. Very few people understand these risks, so they are not being measured or managed appropriately.

Basics of routing and the inherent threats:
-Prefixes
-ASNs
-Routing updates
-Route attributes
-Vulnerabilities & typical historical attacks

Internet Routing – Prefixes
-Internet routing is orchestrated via blocks of IP addresses.
-A network prefix is a block of contiguous IP addresses.
-IP addresses in the same prefix are routed in the same way.

Internet Routing – ASNs
Global Internet routing relies on the Border Gateway Protocol. Each organization participating in BGP is assigned:
-A unique Autonomous System Number or ASN (integer)
-One or more prefixes (range of IP addresses)
-All routing decisions are local

BGP Update Messages
-An UPDATE message announces a new route or withdraws a previously announced route. UPDATE = prefix + route attributes
-Adjacent routers chatter constantly with each other as routes come and go. Globally, Renesys observes 45,000+ updates per minute when things are quiet!

BGP Attributes
Routing announcements have attributes and many possibilities but the (hopefully valid) "AS" path to the announced prefix is always present.

Routing Vulnerabilities
1. No single authoritative source of who should be doing what.
-If there were, you could filter out the errors / hijacks.
-As a result, filtering by ISPs is not common or easy.

2. All of Internet routing is based on trust.
-Anyone can announce any IP space they want.
-Anyone can prepend any ASN to any path that they want.

3. No mechanism in place to handle ASNs who go rogue. There are no Internet police!

Two typical types of hijacks:

No operational impact
-Hijack unused (but maybe assigned) IP space
-Potentially harms the reputation of the owner
-But does not disrupt any legitimate traffic on the Internet
-DoD owns but does not announce 7.0.0.0/8, 11.0.0.0/8, 30.0.0.0/8 and others. These networks
are “free for the taking” without any impact on DoD. Every announcement in this space is a hijack.

Obvious operational impact
-Hijack currently used IP space
-Legitimate traffic diverted to the hijacker
-Victim can be effectively taken off the Internet
-Very disruptive and very obvious
-YouTube owns 208.65.152.0/22 (Feb 2008)
This contains the more-specific 208.65.153.0/24
The above /24 used to contain all of YouTube’s
DNS Servers (have since moved)
Web Servers (have since added additional IP space)
YouTube announced only the /22
-Pakistan Telecom announces the /24
In BGP, most specific route to an IP address wins!
Pakistan Telecom gets all traffic intended for YouTube
YouTube is globally unreachable for 2 hours


Both types of hijack allow an attacker to attract all traffic bound for the hijacked space.

Final Evaluation
-Hijacking has been going on for over 10 years!
-No incremental or comprehensive solutions
-Solutions lack economic drivers
-Doesn’t happen daily and universally
-Avoiding negative publicity is not necessarily compelling
-Impact poorly understood by management
-Miscreants are actively hijacking now
-To send spam from “clean” IP blocks
-To cover their other nefarious activities
-What good are your firewall/IDS logs now?
-Need historical global routing data to identify hijackers

Man-In-The-Middle Attack
-Review the MITM exploit presented at DEFCON 16 (August 10, 2008)
-AS path attribute
-AS loop prevention
-MITM attack technique
-Obscuring the MITM attack with TTL adjustment



How can the victim observe this?
-Victim’s routes and those of at least one provider will look normal
-Traceroute from a public looking glass to the victim’s IPs will show the hijacker
(assuming the looking glass hasn’t been blinded to the attack).
-Traceroute depends on incrementally increasing TTLs
-Hijacker can hide his presence by silently increasing TTLs for packets intended for the victim
-Hides hijacker’s routers
-Hides hijacker’s outbound routes to victim

Detecting the Attack
-Is this generally visible?
-Attacker profile
-Difficulties with detection
-You know the correct routing policies (easy)
-Generally limited to networks under your control
-Review of available alarm services
-Can you attack the alarm services?
-You don’t know the routing policies (hard)
-A proposed global detection technique

Difficulties in observing the MITM attack
-Most Internet routers will see and prefer the hijacked routes. Won’t be obvious among their
270,000+ routes.
-Traceroutes won’t show the hijacking (with TTL adjustments). Independent of source location.
-Latency to the victim will increase. Could be slight if the hijacker isn’t far from the victim.
-Route alarming services might see this if AS loop detection is disabled.

Two simple questions:
Can I detect MITM for my network?
-Easy: Routing policy is presumably known or at least knowable.

Can I detect MITM for the Internet at large?
-Much harder: Routing policies are not known and probably unknowable for all 270,000+ prefixes

Using DAVIX For Security Visualization (revised)


Information visualization
-Visualize large collections of abstract data

Scientific visualization
-Representation of data with geometric structure



Visualization Concept
-Analyzing floods of data in tabular or textual form is tedious
-Humans must sequentially scan such data
-Visualization exploits the human's visual perceptive capabilities and parallel processing Size, Shape, Distance, and Color
-Easy to spot patterns and irregularities

Data types supported
-Ordinal
Has a sequence e.g. day of week
-Nominal
Has no sequence e.g. types of fishes
-Quantitative
Can be measured e.g. length, time, weight, temperature, speed

Visualization Effectiveness
-Each data type has its most effective way of visualization


Information Visualization Process



DAVIX Linux Distribution (http://davix.secviz.org/)
-Provide the audience with a workable and integrated tools set
-Enable them to immediately start with security visualization
-Motivate them to contribute to the security visualization community

Tools Available
Capture
-Network Tools (Argus, Snort, Wireshark)
-Logging (syslog-ng)
-Fetching Data (wget, ftp, scp)

Processing
-Shell Tools (awk, grep, sed)
-Visualization Preprocessing (AfterGlow, LGL)
-Extraction (Chaosreader)
-Data Enrichment (geoiplookup, whois, gwhois)

Visualization
-Network Traffic (EtherApe, InetVis, tnv)
-Generic (AfterGlow, Cytoscape, Graphviz, LGL Viewer, Mondrian, R Project, Treemap)

Interface Transport
-Each visualization tool has its own file format interfaces
-Data must be converted to match the import interfaces
-These adapters are mostly self-written snippets of code

Important Note:
All the images presented in this post are intellectual property of the copyright owner (www.secviz.org)

Scanning SS7 Networks and Telecom Backbones


Historic View
-Phreaking is a term for the action of making a telephone system do something that it normally should not allow.
-Telecommunications security problems started in the 1960’s when the hackers of the time started to discover ways to abuse the telephone company.
-Discovery and exploration of features of telecommunications systems.
-Controlling Network Elements (NE) in a way that was not planned by its designers.
-Abusing weaknesses of protocols, systems and applications in telephone networks.

Fraud Implanted by
-Blue Box
-Internal Fraud

Reliability
-US: 911, Europe: 112
-How much lost revenue is one minute of downtime?

Today's View
-SIP account hacking, remind the "Calling Cards" fraud?
-VoIP GW hacking, remind the "PBX hacking"?
-Signaling hacking directly on SS7 – SIGTRAN level

SS7 Attacks Scenarios
-Theft of service, interception of calling cards numbers, privacy concerns
-Introduce harmful packets into the national and global SS7 networks
-Get control of call processing, get control of accounting reports
-Obtain credit card numbers, non-listed numbers, etc.
-Messages can be read, altered, injected or deleted
-Denial of service, security triplet replay to compromise authentication
-Annoyance calls, free calls, disruption of emergency services
-Capture of gateways, rerouting of call traffic
-Disruption of service to large parts of the network
-Call processing exposed through Signaling Control Protocol
-Announcement service exposed to IP through RTP
-Disclosure of bearer channel traffic

Telecom Backbone



Discovering The Backbone
Deregulation
-Europe / US: CLEC vs ILEC

New services and new business partners
-Premium numbers, SMS providers, etc.

Push toward an “All IP” infrastructure
-Management network
-Cost
-SIGTRAN (SS7 over IP)

SS7 & SIGTRAN
-Core
-Formerly, the walled garden

VoIP
-Edge
-Hard to make it reliable (QoS, SBCs)

SS7 and IP
-There is also exponential growth in the use of interconnection between the telecommunication networks and the Internet, for example with VoIP protocols (e.g. SIP, SCTP, M3UA, etc.)
-The IT community now has many protocol converters for conversion of SS7 data to IP, primarily for the transportation of voice and data over the IP networks. In addition new services such  as those based on IN will lead to a growing use of the SS7 network for general data transfers.
-There have been a number of incidents from accidental action on SS7, which have damaged a  network. To date, there have been very few deliberate actions. Far from VoIP here. 

Attacking SIGTRAN with SCTPscan (http://sctp.tstf.net/)
Where implementation diverge from RFCs
-RFC says "hosts should never answer to INIT packets on non-existings ports".
-Syn scanning is slow when no RST

Below the IDS
-How many firewall logs dropped SCTP packets?
-How many IDS(s) watch for SCTP socket evil content?
-Example: Dshield.org - Real life distributed IDS, Hundreds of thousands of IP scanned, nor detected neither reported as scanner.

INIT vs SHUTDOWN_ACK Packet Scanning
From RFC 2960
-8.4 Handle "Out of the blue" Packets
-An SCTP packet is called an "out of the blue" (OOTB) packet if it is correctly formed, i.e., passed the  receiver's Adler-32 / CRC-32 check (see Section 6.8), but the receiver is not able to identify the association to which this packet belongs.
-The receiver of an OOTB packet MUST do the following:
"If the packet contains a SHUTDOWN ACK chunk, the receiver should respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE."

-New way to elicit answers even if not answering ABORTs to INITs targeted at not-opened port.

SCTP ports (-sS) Stealth Scanning
root@bt:~/sctp# ./sctpscan-v11 --scan --autoportscan -r
203.151.1
Netscanning with Crc32 checksumed packet
203.151.1.4 SCTP present on port 2905
203.151.1.4 SCTP present on port 7102
203.151.1.4 SCTP present on port 7103
203.151.1.4 SCTP present on port 7105
203.151.1.4 SCTP present on port 7551
203.151.1.4 SCTP present on port 7701
203.151.1.4 SCTP present on port 7800
203.151.1.4 SCTP present on port 8001
203.151.1.4 SCTP present on port 2905
root@bt:~/sctp#

SCTP Stack Fingerprinting
-SCTP stack reliability
-Robustness testing (stress testing)
-QA of a few stacks
-Fuzzing built-in SCTPscan
-Discrepancies in SCTP answer packets
-Different stack behaviours
-Much more states than TCP=opportunities
-Cookie randomness

Analyzing Side Channel Attacks on Embedded Systems


General embedded systems based on micro-controller and complex processors:
-USB sticks
-Car locks
-Remote access tokens
-Mobile devices
-Game consoles
-Multi-media chipsets for pay-TV

Think of Security:
-What is the threat from side channel analysis to embedded systems?
-How does it compare with attacks on smart cards?
-What are the future developments?

Attacking Side Channels
-Time
-Power consumption
-Electro-Magnetic radiation
-Light
-Sound

Power/EM traces
-Signal leakage from busses, registers, ALUs, etc.

Statistical data detection
-Where is data processed in presence of noise?
-Collect many traces with different data (n > 1000)
-Assume data values are:
    known (e.g. algorithm input or output)
    uniformly random (typical for crypto)
-We focus on one bit of one variable in the process


Differential trace
-Input: n traces with known variable (e.g. input or output)
-Output: 1 trace with indication where bit causes trace differences

Purpose of Side Channel Attacks on Embedded Systems
-Retrieve secrets (Key, PIN, Unlock code)
-Reverse engineer (Program flow, Crypto protocol, Algorithm)

Why Side Channel Attacks are interesting? If side channel threats depends on:
-Physical access?
-Access time window?
-Interfacing and control?
-Exploitation equipment $?

A device becomes interesting when:
-It contains a secret
-It contains a feature that can be unlocked
-Logical or physical access to internals is hard

Typical Side Channel Attack Example



Typical Prerequisites
-Access to side channel
-Access to input or output data
-Minimize noise in side channel
-Time measurement of operation (trigger)
-Link data to operation

Processor comparison with Smart Card
 
Acquisition comparison with Smart Card


Test vs. Attack
-An attacker needs to turn a vulnerability into an exploit
-A tester needs to gain insight in attacker cost efficiently
-How to create the optimal environment to discover a vulnerability?

General aspects of testing
-Controlling the crypto
-Linking data with measurements
-Efficiency of acquisition
-Increased speed versus increased complexity

Timing analysis
-Peripheral outputs assist (example XBOX 360)
-Exploiting runtime access (cache)
-Increasing accuracy with EM and power
-Timing is a risk in many software implementations: both crypto and comparisons

XBOX 360 with Backdoor

 -XBOX 360 has a secure boot chain
-First boot loader security implemented with a HMAC-SHA1
-Hash secret key + boot loader with SHA1
-Compare 16 bytes result with stored 16 bytes
-Comparison is per byte -> timing attack
-Implementation in this infectus board:
    It can modify stored HMAC-SHA1 value in NAND flash
    Observes timing of diagnostic POST byte on PCB
    Reset CPU with nTRST
-Brute forcing 16*128 = 2048 values on average takes about 2 hrs

Power analysis
-Tapping power or supplying it
-Reaching rails
-Identifying the correct supply rail
-Disabling power domains
-Disabling peripherals
-All require more detailed knowledge on target

EM (Electro Magnetic) Analysis
-EM signal adds dimension
-How to locate?
-When can EM be better?
-EMA is an active research topic
-EM seems to add most when target operation is small relative to overall chip

Threat and Impact
-Few countermeasures
-Significant leakage
-Fast acquisition
-Required level of control
-Attacks needed to achieve control
-High noise level, increased acquisition times

Countermeasures
Hardware
-Random Interrupts
-Data / Key masking
-Shielding
-Balancing

Software
-Randomizing flow
-Blinding / Masking
-Algorithm
-Protocol design

Analyzing Malware Through MS-Office Documents

Key Highlights
-MS Office commonly exploited since 2006
-Existing exploits in the wild exploit unexceptional the older OLESS file format.
-Currently no known bugs in the newer XML based MS Office format.

Some MS Office exploits since 2006
-CVE-2006-0009 Powerpoint MS06-012 (March 2006)
-CVE-2006-0022 Powerpoint MS06-028 (June 2006)
-CVE-2006-2492 Word MS06-027 (June 2006)
-CVE-2006-3434 Powerpoint MS06-062 (October 2006)
-CVE-2006-3590 Powerpoint MS06-048 (August 2006)
-CVE-2006-4534 Word MS06-060 (October 2006)
-CVE-2006-4694 Powerpoint MS06-058 (October 2006)
-CVE-2006-5994 Word MS07-014 (February 2007)
-CVE-2006-6456 Word MS07-014 (February 2007)
-CVE-2007-0515 Word MS07-014 (February 2007)
-CVE-2007-0671 Excel MS07-015 (February 2007)
-CVE-2007-0870 Word MS07-024 (May 2007)
-CVE-2008-0081 Excel MS08-014 (March 2008)
-CVE-2008-4841 Word MS09-010 (April 2009)
-CVE-2009-0238 Excel MS09-009 (April 2009)
-CVE-2009-0556 Powerpoint MS09-017 (May 2009)

Generic OLESS Format
-OLESS Header
-FAT FS: SectorNumbers, OLESS directory entries
-Data is divided into directories (storages) and files (streams)
-Depending on the application streams may contain: Macros, Graphics, Tables, Sounds, Animations, etc.
-Parsing can be done using the Win32 COM API: StgOpenStorage(), IStoragemethods, IStreammethods.

Malicious Document Structure

Typical MS-Office Shellcode Behavior

When a bug in a MS Office application gets triggered:
-Shellcode executes
-Finds itself by open file handles enumeration and file size checking
-SetFilePointerto encrypted PE-File(s), decrypt, drop and execute
-Drop harmless embedded MS Office document and start to look innocent

More information:
-Not much public information about MS-Office malware analysis available
-Microsoft Office Binary File Format Specification (since Feb. 2008)
-Bruce Dang's talk "Methods for Understanding Targeted Attacks with Office Documents".

Available Tools For Analysis
-DFView (old school Microsoft OLE structure viewer)
-Officecat (signature based CLI utility)
-FlexHexEditor (OLE compound viewer)
-OffVis (office binary file format visualization tool)
-OfficeMalScanner (forensic tool for analysts to find malicious traces in MS Office documents)

Wireless Reconnaissance in Practice

Kismet (stable, devel and newcore) 
Locate / Identify AP(s)
-BSSID, ESSID, Channel and Encryption
-GPS data
Locate / Identify Client(s)
-MAC Address
-Manufacturers
Perform Spectrum analysis
Drones / open-source WIPS

Aircrack-ng – Cracking WEP and WPA
-Suite of tools for wireless testing
-Mostly thought for wireless cracking
-Can also be used for wireless recon
-IE Airodump-ng

Netstumbler
-All for the Win32 geeks.

Types Reconnaissance Data
Kismet-(stable|devel) – Txt, CSV, XML, GPS and pcap
Kismet-newcore – Txt, NetXML, GPS and pcap
Aircrack-ng – CSV, pcap, XML

Wireless Recon Visualization Tools
-Gpsmap (ancient)
-Pykismet
-Kismet-earth
-kisgearth

Limitations of Visualization Tools
-None work with Kismet-newcore
-None work with Aircrack-ng
-Flexible representation of specific information (total flexibility in the generated graphs).

Targeting SAP Platform Using Trojans and Rootkits


Typical Enterprise Environment
-Has more than a thousand of employees
-Is a circus of IT Systems
–Mixture of operating systems, databases, applications and their different versions
-Decision makers care more about their bonus than the interest of the company
-Is a political battlefield

Enterprise Security
Even a medium level of IT security is too expensive to achieve
–Missing asset management (how many Oracle DBs, Windows servers, etc)
–Tons of security scanning, to few remediation chasing
–Many of the vulnerabilities cannot be mitigated
-Obsessed by Cross Site Scripting
-IT security departments cannot influence security decisions of business applications much, because of political reasons.
-Nobody cares about the hacked UNIX machine, SQL DB, or others.
-Defacement and similar security incidents are budget approvers

SAP Systems
-Business specific
-Industry solutions
-Hold the Crown Jewels
-Are usually extensively customized
-Less exposure to typical hackers (ABAP)

SAP Security
-Security mostly focuses on authorizations and segregation of duties
-Intrusion prevention is still a baby
-Risks are underestimated/general IT Security efforts are typically unbalanced at companies
-Unlike e.g Active Directory, SAP systems belong to the business, not the IT
-Security departments usually fail when they are challenged



RFC (Remote Function Call) protocol lets you run functions remotely
–To run; use Java, C, etc. with RFC-SDK or simply execute the test program "startrfc". Following
creates a new user with god rights:

startrfc -3 -h 10.1.5.4 -s 05 -c 010 -u ERTUNGA -p CCC42 -F SUSR_RFC_USER_INTERFACE
-E USER=SATRIANI -E ACTIVITY=01 -E PASSWORD=RUBINA -E USER_TYPE=A -T USER_PROFILES,
12,r=-SAP_ALL


There is no exploit involved. Everything is intended functionality.
–Beats "RFC users are not a threat because they cannot login via SAPGUI"
–Time to recheck company’s shared folders and eliminate hardcoded passwords.

RFC (a.k.a communication) users are thus very very important!
–Secure their passwords and make them part of the password change process
–Don’t forget: GUI (dialog) users which have S_RFC rights can also execute remotely
–SAP_ALL FOR COMMUNICATION USERS IS A NO GO!

RFC_READ_TABLE
Reads the contents of any table (Including ones with sensitive data e.g salary information)
Has bugs in converting e.g binary fields

SUSR_RFC_USER_INTERFACE
Can be used for creating/modifying users

RFC_ABAP_INSTALL_AND_RUN
-Takes ABAP source lines and executes them
-Widely known! tighten user authorizations to prevent abuse
-More restricted in latest NetWeaver Systems

RFC can be encapsulated in SOAP messages (SOAP RFC)
-Company’s internal proxy suddenly opens the doors to all SAP systems
-Disable it if not used!

Single Sign-on (SSO2)
-Is a convenient feature, not a security feature
-RTFM: Secure Store and Forward [SSF] documentation
-Personal Security Environment files hold the private key data
-If an attacker obtains it, it can create authentication tickets for the victim system. Accepting these tickets is enabled per default. Attacker can logon as any user.
-The private key container (PSE) can be pin-protected
-Advice: Disable accepting tickets using relevant profile parameters!

SQL Injection-ABAP typically uses parametrized queries (Developers can still specify parts of sql statements dynamically by parentheses)
-Not dynamic: SELECT ColumnA FROM TableA INTO[...]
-Dynamic: SELECT(var_ColumName)FROM(var_TableName) INTO[...]WHERE(var_WhereClause)
-Avoid dynamic statements where possible!

Cross Site Scripting
-Proper sanitization/encoding of the input data is the key for self developed web code such as BSPs.
-If not done, an attacker can do everything related to XSS, plus steal e.g the SSO2 (Authentication) cookies from the clients SSO2 cookies are stateless so client impersonation is a breeze. Avoid using this mechanism without proper controls.
-If you have F5's or similar devices, encrypt cookies based on origin IP.

ABAP Executable Manipulation
-Statement: INSERT REPORT
-Writes custom code to any ABAP program
-It's even possible to call an editor to make it more user friendly
-Very suspicious if found in self-developed code

RS_REPAIR_SOURCE Executable
-Unpatched version does not have authorization checking.
-People with e.g SE38 rights can execute this and manipulate the system and data of it.
-Same as ABAP injection, only more convenient.
-SAP patched it via: SAP Note 1167258: Program RS_REPAIR_SOURCE

ABAP Rootkits
-It is possible to modify system executables (ABAPs)
-An attacker can easily infect important ones executables and install an ABAP rootkit
-SAP has RFC functions that do not require user authentication by default (SRFC Function Group). This could be one candidate.
-Installed rootkit can give anonymous access to the attacker with functionality such as: Installing
SAP_ALL users, Manipulating ABAP reports, Running OS commands, Stealing hashes or PSE files, Deleting Logs.

Triple-Penetration Attacks
Penetration 1: Attacker exploits the weakest system
-Typical enterprise setup: Testing/Development ­> Quality Assurance ­> Production
-Among them, most unprotected are test/development systems

Penetration 2: Attacker infects clients which connect to the weakest system
–Starts with modification/infection of the critical areas such as logon screen ABAP code
-When admins/developers successfully login, malicious payload is downloaded and executed on these users computers

Penetration 3: Victim infects all the systems it later connects to
-Modification of critical components of the newly accessed SAP systems (Internal production systems, Partner systems, critical systems)



How to stay secure
-Have proper "check-in" and "leavers process" that take the ABAP developer risks into consideration
-Audit the code against security vulnerabilities before transporting to production systems
-Syncing passwords to development systems means, possibility of developers to capture valid passwords for production systems. Avoid it!
-Get rid of insecure and/or default passwords
-Disable backwards compatiability of passwords
-Install the latest security patches

Ineffectiveness of AntiVirus Solutions

Many recent high profile attacks into major software companies, public sector institutions and international organizations.
–Aurora attack on Google and 32 other companies last year
–In all cases: malicious email was sent to victim

Email-borne threats fall into two general categories:
–Mass email attacks
–Targeted attacks
Traditional AV increasingly ineffective and heuristic engine is necessary.

Typical Bredolab/Trojan.Sasfis
Most prolific family of mass-mailed threats using executable attachment.
Social engineering lures:
–Social Media website password reset
–Western Union or UPS invoice
–"You have received an E-Card!"
–Spammed out in very large numbers (Cutwail botnet)
–Many different payloads
–13.3% of all Malware stopped by Skeptic
–Between June 2009 and June 2010 (excluding Phish and links)
–Typically low AV detection (< 10 on VT)
–Good social engineering tactics
–Use of Word or Excel icons
–Spoof prolific companies (Facebook, UPS, Fedex)
–Heavy use of server-side polymorphism (SSP) to evade signature-based AV




Signature-based AV
–Create a "signature" for a piece of Malware
–String(s) of bytes
–Checksum(s)
–Very specific
–Evidence of increased use of SSP
–In 2008, Symantec created 1,691,323 new malicious code signatures
–In 2009, 2,895,802 new signatures were created (71% increase)
–139% increase from 2007 to 2008
–Not sustainable!
–Solution: heuristic-based approach

Signature Development Process


Heuristic-based Approach
–Generic detection
–Features known to exist in Malware
–Decision based on extracted features
–Weighted
–Cloud based
–no reactive signature deployment delays

Polymorphic Viruses
–Big problem for AV
–Many different variants
–Functionally equivalent
–Signatures required for each variant
–Solution: "emulation"
–Emulate past decryptor stub
–Sig the static virus body

Server-side polymorphism (SSP)
–Custom encryption routine
–Decrypt at runtime
–Generated by a polymorphic engine
–Hundreds or perhaps thousands of unique variants
–Random junk instructions
–API calls
–Arithmetic
–EP

Use in mass-email attacks
–Attackers generate a number of unique binaries
–Change the binary being spammed throughout the attack
–Problem for any vendor without proactive protection in place

Bredolab Case Study - 30 March 2010
–Standard Bredolab run:
–Subject: variation of 'UPS Delivery Problem NR 18800'
–Attachment: similarly named 'UPS_invoice_1845.exe'
–relatively small (only 56 observed copies)
–Started at 19:08:33 GMT (time 0)
–Last observed sample at 19:36:31
–Total of 27 min 59s

Case Study - AV Detection & Response Time
–At time 0, AV detection was 0
–Average response time?
–661 minutes (11 hours and 1 minute)
–Remember that the attack only lasted 28 mins
–This is the average response time
–INEFFECTIVE

Aurora and Targeted Attacks (Spear-Phishing)
–Aurora/Hydraq
–Up to 34 different companies compromised in same period using similar techniques
–Email links to malicious web pages
–Flaws in Adobe Acrobat Reader
–Google hackers are back?
–CVE-2010-2883

According to US Department of Defense Cyber Crime Center:
"102 breaches of the Pentagon’s agencies, partners and contractors in a two-year period ending August 2009"




Targeted Attack Case Study - 24 March 2010
–Targeted attack blocked attempting to exploit CVE-2010-0188 (libTiff)
–Single copy sent to an individual in a major international organization
–Co-ordinates governments from around the world
–Trojanized a clean PDF from a World Cup travel site

Case Study - AV Detection & Response Time
–AV detection was 0
–One week later, AV detection at 33%
–Sample sharing, blogged
–Average response time?
–3631 minutes (two and a half days)
–Only takes into account the 33% of vendors that were actually detecting the threat
–INEFFECTIVE