What type of voice mail security issue is characterized by unauthorized access and potential monetary loss?

Toll fraud is a specific type of voice mail security issue that involves unauthorized access to a phone system, allowing an attacker to make unauthorized long-distance calls, which can lead to significant monetary loss for the victim. In this scenario, the fraudster typically gains access to a voicemail system or a telephone network without permission, manipulating it to rack up high charges while typically running up these costs under the owner's account.

This type of fraud is concerning because it can occur without the victim's knowledge until the bill arrives, highlighting the importance of securing telecommunications systems. Protecting against toll fraud involves implementing strong passwords, regularly updating security protocols, and ensuring that call records are monitored for unusual activity.

In contrast, while data interception, identity theft, and system overload are all important security issues, they do not directly describe the specific monetary loss related to unauthorized phone calls that defines toll fraud.