What does SLE stand for in loss expectancy?

• A. Single Loss Event
• B. Single Loss Expectancy
• C. Security Loss Event
• D. System Loss Evaluation

Answer: (B)

In risk assessment for information security, you quantify the financial impact of a single incident with a metric that represents the loss from one event. This is called Single Loss Expectancy. It reflects the monetary amount you could lose from a single occurrence of a threat exploiting a vulnerability. A common way to think about it is: if an asset is worth a certain amount and a specific incident could cause a portion of that value to be lost, the SLE is that portion. For example, if an asset is valued at $100,000 and a single event could cause a 25% loss, the SLE would be $25,000. This value helps compute broader risk metrics, like annualized loss expectancy, by combining it with how often the event is expected to occur. The other terms listed aren’t the standard way to denote the loss from one incident. They don’t capture the monetary impact of a single loss event in the same way.