Top Security Controls Ranked by ROI
Not all security controls deliver equal value. When budgets are limited, CISOs must prioritise controls that deliver the most risk reduction per dollar spent. Here are the controls that consistently rank highest on ROI.
1. Multi-Factor Authentication (MFA)
MFA remains the single highest-ROI security control. Microsoft research shows MFA blocks over 99% of account compromise attacks. At a relatively low cost per user, MFA delivers outsized reduction in phishing, credential theft, and unauthorised access scenarios.
2. Security Awareness Training
Ponemon and KnowBe4 research shows that structured training programmes reduce phishing click rates by 54% within six months and up to 86% within a year. The cost is modest relative to the reduction in human-error-driven breaches.
3. Email Security Gateway
Advanced email filtering stops threats before they reach users. Combined with MFA and training, an email gateway creates a strong defensive layer against the most common attack vector — phishing and business email compromise.
4. Backup and Recovery
Immutable backups with tested recovery procedures dramatically reduce ransomware impact. Organisations with reliable backups can decline ransom demands and recover operations faster, often turning a multi-million-dollar incident into a manageable disruption.
5. Vulnerability Management
Continuous scanning and patching addresses the known vulnerabilities that attackers most frequently exploit. The cost of a vulnerability management programme is a fraction of the breaches it prevents.
The Diminishing Returns Factor
Each additional control targeting the same risk scenario delivers less marginal benefit. The fifth phishing control does not reduce risk as much as the first. Prioritise breadth of coverage across risk scenarios before depth in any single area.