How does a signature-based scanner find malware?

A signature-based scanner identifies malware by comparing the code of applications to a comprehensive database of known malware signatures. These signatures are unique identifiers or patterns derived from previously identified malware samples. When a file or program is scanned, the scanner analyzes its code and checks for matches against the database. If a match is found, the scanner can identify the file as malware based on this comparison.

This method is effective because it relies on established, recognized identifiers of malware that have been cataloged over time. Signature-based scanning is typically fast and efficient, but its effectiveness is contingent upon the comprehensiveness and currency of the signature database. It is particularly strong at detecting known threats but may fail to identify new or unknown malware that has not yet been added to the database.

The other methods mentioned in the other choices involve different approaches to detecting malware, such as behavior-based detection or network monitoring, which are distinct from the signature-based approach. These alternative methods do not rely on pre-existing signatures but instead focus on identifying suspicious actions or traffic patterns.