What does PCI-DSS requirement 5.1 mandate regarding anti-virus software?

The requirement 5.1 of the PCI-DSS (Payment Card Industry Data Security Standard) mandates that anti-virus software must be deployed on all systems that are susceptible to malware. This is crucial for maintaining the security of cardholder data and protecting systems against various types of malicious software, which can compromise sensitive information.

By ensuring that anti-virus solutions are in place on all potentially vulnerable systems, organizations significantly reduce the risk of malware infections that can lead to data breaches. This requirement emphasizes the importance of a comprehensive security posture where protection mechanisms are not limited to a subset of systems but are rather universally applied to all relevant environments.

This approach helps to ensure that every system that processes or stores sensitive payment information is adequately defended against evolving malware threats, reinforcing the overall security framework mandated by PCI-DSS.