Hack Proofing Your Network: The Only Way to Stop a Hacker is to Think Like One 2nd Ed.
Nessus, Snort, & Ethereal Power Tools: Customizing Open Source Security Applications
PCI Compliance: Understand and Implement Effective PCI Data Security Standard Compliance
Penetration Tester's Open Source Toolkit
Sarbanes-Oxley IT Compliance Using Open Source Tools: A Toolkit for IT Professionals 2nd Ed.
Special Ops: Host and Network Security for Microsoft, UNIX, and Oracle