There is no single frequency that fits every organisation. The right schedule depends on how quickly your environment changes, what is exposed to the internet and how much assurance your customers, insurers or leadership team require.
An assessment is a point-in-time view
A well-run assessment shows what was visible during the agreed testing window. After that date, new vulnerabilities are disclosed, software changes, devices are added and configuration can drift.
This does not make annual assessments useless. It means the business should understand the period of risk between reviews and choose a cadence deliberately.
Factors that should drive frequency
- The number and importance of internet-facing systems
- How often infrastructure and applications change
- Customer, contractual and cyber insurance requirements
- The sensitivity of information and services involved
- Internal capacity to remediate and verify findings
- Previous assessment results and recurring weaknesses
A practical starting cadence
For a relatively stable small environment, an annual independent assessment can establish a baseline, provided critical changes and emerging issues are handled between reviews. Organisations with more exposed or frequently changing systems may benefit from quarterly or monthly vulnerability management.
A useful program also triggers assessment after material events such as a major infrastructure change, acquisition, new public service or significant security incident.
Frequency is only useful when findings move
Running tools more often does not automatically reduce risk. Someone must review the findings, assign ownership, track remediation and confirm whether fixes worked. A modest but accountable program is more valuable than constant scanning without action.