Introduction xxiii
Chapter 1 Web Application (In)security 1
The Evolution of Web Applications 2
Web Application Security 6
Summary 15
Chapter 2 Core Defense Mechanisms 17
Handling User Access 18
Handling User Input 21
Handling Attackers 30
Managing the Application 35
Summary 36
Questions 36
Chapter 3 Web Application Technologies 39
The HTTP Protocol 39
Web Functionality 51
Encoding Schemes 66
Next Steps 70
Questions 71
Chapter 4 Mapping the Application 73
Enumerating Content and Functionality 74
Analyzing the Application 97
Summary 114
Questions 114
Chapter 5 Bypassing Client-Side Controls 117
Transmitting Data Via the Client 118
Capturing User Data: HTML Forms 127
Capturing User Data: Browser Extensions 133
Handling Client-Side Data Securely 154
Summary 156
Questions 157
Chapter 6 Attacking Authentication 159
Authentication Technologies 160
Design Flaws in Authentication Mechanisms 161
Implementation Flaws in Authentication 185
Securing Authentication 191
Summary 201
Questions 202
Chapter 7 Attacking Session Management 205
The Need for State 206
Weaknesses in Token Generation 210
Weaknesses in Session Token Handling 233
Securing Session Management 248
Summary 254
Questions 255
Chapter 8 Attacking Access Controls 257
Common Vulnerabilities 258
Attacking Access Controls 266
Securing Access Controls 278
Summary 284
Questions 284
Chapter 9 Attacking Data Stores 287
Injecting into Interpreted Contexts 288
Injecting into SQL 291
Injecting into NoSQL 342
Injecting into XPath 344
Injecting into LDAP 349
Summary 354
Questions 354
Chapter 10 Attacking Back-End Components 357
Injecting OS Commands 358
Manipulating File Paths 368
Injecting into XML Interpreters 383
Injecting into Back-end HTTP Requests 390
Injecting into Mail Services 397
Summary 402
Questions 403
Chapter 11 Attacking Application Logic 405
The Nature of Logic Flaws 406
Real-World Logic Flaws 406
Avoiding Logic Flaws 428
Summary 429
Questions 430
Chapter 12 Attacking Users: Cross-Site Scripting 431
Varieties of XSS 433
XSS Attacks in Action 442
Finding and Exploiting XSS Vulnerabilities 451
Preventing XSS Attacks 492
Summary 498
Questions 498
Chapter 13 Attacking Users: Other Techniques 501
Inducing User Actions 501
Capturing Data Cross-Domain 515
The Same-Origin Policy Revisited 524
Other Client-Side Injection Attacks 531
Local Privacy Attacks 550
Attacking ActiveX Controls 555
Attacking the Browser 559
Summary 568
Questions 568
Chapter 14 Automating Customized Attacks 571
Uses for Customized Automation 572
Enumerating Valid Identifiers 573
Harvesting Useful Data 583
Fuzzing for Common Vulnerabilities 586
Putting It All Together: Burp Intruder 590
Barriers to Automation 602
Summary 613
Questions 613
Chapter 15 Exploiting Information Disclosure 615
Exploiting Error Messages 615
Gathering Published Information 625
Using Inference 626
Preventing Information Leakage 627
Summary 629
Questions 630
Chapter 16 Attacking Native Compiled Applications 633
Buffer Overflow Vulnerabilities 634
Integer Vulnerabilities 640
Format String Vulnerabilities 643
Summary 645
Questions 645
Chapter 17 Attacking Application Architecture 647
Tiered Architectures 647
Shared Hosting and Application Service Providers 656
Summary 667
Questions 667
Chapter 18 Attacking the Application Server 669
Vulnerable Server Configuration 670
Vulnerable Server Software 684
Web Application Firewalls 697
Summary 699
Questions 699
Chapter 19 Finding Vulnerabilities in Source Code 701
Approaches to Code Review 702
Signatures of Common Vulnerabilities 704
The Java Platform 711
ASP.NET 718
PHP 724
Perl 735
JavaScript 740
Database Code Components 741
Tools for Code Browsing 743
Summary 744
Questions 744
Chapter 20 A Web Application Hacker’s Toolkit 747
Web Browsers 748
Integrated Testing Suites 751
Standalone Vulnerability Scanners 773
Other Tools 785
Summary 789
Chapter 21 A Web Application Hacker’s Methodology 791
General Guidelines 793
1 Map the Application’s Content 795
2 Analyze the Application 798
3 Test Client-Side Controls 800
4 Test the Authentication Mechanism 805
5 Test the Session Management Mechanism 814
6 Test Access Controls 821
7 Test for Input-Based Vulnerabilities 824
8 Test for Function-Specific Input Vulnerabilities 836
9 Test for Logic Flaws 842
10 Test for Shared Hosting Vulnerabilities 845
11 Test for Application Server Vulnerabilities 846
12 Miscellaneous Checks 849
13 Follow Up Any Information Leakage 852
Index 853
