11.2.1 Perform quarterly internal vulnerability scans. Address vulnerabilities and perform rescans to verify all “high risk” vulnerabilities are resolved in accordance with the entity’s vulnerability ranking (per Requirement 6.1). Scans must be performed by qualified personnel.
11.2.1.a Review the scan reports and verify that four quarterly internal scans occurred in the most recent 12- month period.
11.2.1.b Review the scan reports and verify that all “high risk” vulnerabilities are addressed and the scan process includes rescans to verify that the “high risk” vulnerabilities (as defined in PCI DSS Requirement 6.1) are resolved.
11.2.1.c Interview personnel to verify that the scan was performed by a qualified internal resource(s) or qualified external third party and, if applicable, organizational independence of the tester exists (not required to be a QSA or ASV).
An established process for identifying vulnerabilities on internal systems requires that vulnerability scans be conducted quarterly.
Vulnerabilities posing the greatest risk to the environment (for example, ranked “High” per Requirement 6.1) should be resolved with the highest priority.
Internal vulnerability scans can be performed by qualified, internal staff that are reasonably independent of the system component(s) being scanned (for example, a firewall administrator should not be responsible for scanning the firewall), or an entity may choose to have internal vulnerability scans performed by a firm specializing in vulnerability scanning.