Michael Howard, David LeBlanc and John Viega have written a book called The 19 Deadly Sins of Software Security, which is to be published soon.
It explains the most important security issues one encounters in the software industry in a Design Patterns-like format. Each software security Sin is structured according to the following sections: Overview, The Sin Explained, Sample Code Defect, Spotting the Defect Pattern, Spotting the Defect during Code Review, Testing the Defect during Test, Example Defects, Redemption Steps, Extra Defensive Measures, Other Resources, Summary.
The 19 chapters, or Sins, each 10-15 pages long:
(via Dana Epp)