What characteristic of polymorphic viruses complicates their detection?

Polymorphic viruses are specifically designed to evade detection by frequently altering their code or structure while maintaining their overall functionality. This characteristic allows them to create numerous variations of themselves with each infection cycle, making traditional signature-based detection methods significantly less effective. Since antivirus solutions often rely on a database of known virus signatures to identify malware, the ability of polymorphic viruses to change their appearance at each iteration complicates the identification process.

By consistently modifying their code, these viruses can bypass security measures that rely on static detection techniques. This presents a formidable challenge for cybersecurity professionals, as they must employ more advanced detection methods, such as behavioral analysis or heuristic approaches, to effectively combat these resilient threats.

The other characteristics mentioned, although potentially relevant in different malware contexts, do not specifically address the unique evasion tactics employed by polymorphic viruses in the same way.