Software Security Without The Source Code By Matt Hargett

Introduction ➲ Matt Hargett ● Security QA Engineer for 7 years ● NAI/McAfee, TurboLinux, Cenzic ● Discovered many critical vulnerabilities ● Created binary code analysis product ● BugScan

Overview ➲ Why we need to measure software security ➲ Kinds of security policy testing ➲ Whitebox approaches ➲ Blackbox approaches ➲ Effectiveness against real-world exploits ➲ What you can do with this information

Why we need to measure ➲ Brand and reputation damage ➲ Proprietary information leakage ➲ Unplanned disruption ➲ Violation of privacy policy ➲ Espionage ➲ Terrorism

How do we measure ➲ Whitebox ● Manual code inspection ● Source code static analysis ● Binary static analysis ● Runtime analysis ➲ Blackbox ● Web Applications ● Network protocols ● APIs

Blackbox Network Testing ➲ Sniff, fuzz, replay ● Sniff network traffic ● Systematically fuzz the relevant data ● Remove delimeters, bitwalk,... ● {admin.command\0::\43\89\42} ● Replay fuzzed packets to server ➲ Fuzzing via Proxy ● Route traffic through a proxy ● Proxy fuzzes data systematically ● Fuzzed data gets passed on ● Repeat client operation ➲ Protocol-specific fuzzing ● Make special client for specific protocol(s)

Blackbox Network Testing: In the Real World ➲ Sniff, fuzz, replay ● Not stateful ● Doesn't work with encryption ● Only fuzzes client-side ➲ Fuzzing via Proxy ● Lets real client/server handle state ● Doesn't work with encryption ● Fuzzes client and server data ➲ Protocol-specific fuzzing ● Handles real state of client/server ● Does encryption itself ● Can get great code coverage ● Fuzzes client server and data

Blackbox Network Testing: General Jeers ➲ Detecting when you've evoked a problem ➲ Measuring code coverage ➲ Slow process ➲ Expensive to scale

Blackbox Web Testing ➲ Sniff, fuzz, replay ● Auto-crawl or manual clicks ● Sniff browser requests ● Systematically fuzz the relevant data ● Insert SQL Injection, Command Injection, XSS,... ● POST /foo.cgi?name=bob&pass=... ➲ Fuzzing via Proxy ● Optionally crawl to generate requests ● Send requests through a proxy ● Proxy fuzzes requests systematically ● Repeat browser operation ➲ GUI Automation tools ● Automate real browser interaction ● Put bad data into form and cookie fields

Blackbox Web Testing: In the Real World ➲ Sniff, fuzz, replay ● Server-side state mishaps ● Little to no javascript support ● No flash, java, web service support ● Finds WAY low-hanging fruit ➲ Fuzzing via Proxy ● Server-side state mishaps ● Must have browser automation anyways ● Operations must be self-contained ➲ GUI Automation tools ● Maintenance of stored tests ● Tests must be self-contained ● Can be part of standard QA

Blackbox Web Testing: General Jeers ➲ Detecting when you've evoked a problem ➲ Measuring code coverage ➲ Slow process ➲ Expensive to scale ➲ Getting past captchas

Whitebox Testing Without Source ➲ Manual review ➲ Call-based static analysis ➲ Pointer and control/data flow static analysis

Whitebox Testing Without Source: In the Real World ➲ Manual review ● Going through instruction by instruction ● Tedious, time consuming, error prone, rare skill ● Pair rev-enging, unit testing ● Rare skill, unit test exploits may not be real-world ➲ call-based analysis ● 42,897 strcpy calls detected!!!!#%* ● HttpResponse.GetValue() before Statement.Execute() ● Dispose called inside Dispose ➲ Pointer and control/data flow analysis ● Must be inter-function to be useful ● Must track global/static data ● Inter-module tracking also important

Whitebox Testing Without Source: General Jeers ➲ People ● Hire manual reviewers with a proven track record of real- world exploitable bugs patched by a vendor ➲ Tools ● Difficult to use ● Poor quality ● False positives

Whitebox Testing With Source: General Jeers ➲ Worthless when source not available ➲ People ● Hire manual reviewers with a proven track record of real- world exploitable bugs patched by a vendor ➲ Tools ● There is no free unit test lunch ● Demand vendors demonstrate finding novel real-world exploitable bugs their tool finds OOTB ● Demand vendors demonstrate finding previously known real-world exploitable bugs their tool finds OOTB ● Demand third party vendor-neutral benchmarks ● No good visualization/exploration tools for manual reviewers

Whitebox Testing: General Jeers, Source or Not ➲ Code is code, period ➲ Most tools are a retarded joke ➲ False positive rates above 10% on large (100KLOC) means a useless tool ➲ High priority report items should be real-world exploitable 95% of the time ➲ Custom signatures shouldn't require extra cost, permission, or license ➲ Tools ● Demand vendors demonstrate finding novel real-world exploitable bugs their tool finds OOTB ● Demand vendors demonstrate finding previously known real- world exploitable bugs their tool finds OOTB ● Demand third party vendor-neutral benchmarks ● No good visualization tools for manual reviewers ● Zealousy on a given approach

Recommendations ➲ Engage a holistic approach ● Blackbox and Whitebox ➲ Use multiple vendor tools to cross-check ● Source and binary ● Runtime and static ➲ Use protocol-specific fuzzers ● Ask vendor for code coverage on open source implementation(s) of said protocol(s) ➲ Use UI automation tools for web apps ➲ Any good tool will require tuning

Taking Action ➲ If open source, fix the problem yourself ➲ Contact vendor ➲ If vendor cannot supply a fix in 30 days ● Escalate the issue ● Find a new vendor ● If open source, fix the problem yourself ➲ Vendors will string you along

Thank You use. net Questions?