Lecture 23: May 22, 2026

Reading: text, §24.2–24.5
Assignments: Homework 4, due May 27, 2026

1. Greetings and felicitations!

2. Penetration Studies
   1. Goals
   2. Where to start
      1. Unknown system
      2. Known system, no authorized access
      3. Known system, authorized access

3. Flaw Hypothesis Methodology
   1. System analysis
   2. Hypothesis generation
   3. Hypothesis testing
   4. Generalization

4. System Analysis
   1. Learn everything you can about the system
   2. Learn everything you can about operational procedures
   3. Compare to other systems

5. Hypothesis Generation
   1. Study the system, look for inconsistencies in interfaces
   2. Compare to other systems’ flaws
   3. Compare to vulnerabilities models

6. Hypothesis testing
   1. Look at system code, see if it would work (live experiment may be unneeded)
   2. If live experiment needed, observe usual protocols

7. Generalization
   1. See if other programs, interfaces, or subjects/objects suffer from the same problem
   2. See if this suggests a more generic type of flaw

8. Elimination

9. Examples
   1. Michigan Terminal System
   2. Burroughs B6700 System
   3. Corporate computer system

Matt Bishop Office: 2209 Watershed Sciences Phone: +1 (530) 752-8060 Email: mabishop@ucdavis.edu

ECS 153A, Computer & Information Security & Privacy I Version of May 22, 2026 at 3:33PM

You can also obtain a PDF version of this.