We've all seen them - software agents lurking in our system trays. They're useful for all kinds of stuff from antivirus and backup to systems management. However, as Thomas Ptacek at Matasano Security points out, blind usage of agents without considering the potential for vulnerabilities can cause disaster.

Some problems with agents:

• Agents often run with system privileges
• Agents often form a communication mesh through which they could be exploited
• Some software providers don't follow secure programming practices
• An exploit for a system agent can be cross-platform due to a single code base

Check out the article from Matasano linked below and if you have more time, read Richard Bejtlich's response at Taosecurity.