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Patch Management
Definition
Patch management is the systematic identification, testing, and installation of software updates (patches) to close known security vulnerabilities. It is one of the most effective measures to prevent cyberattacks.
Patch management is the systematic identification, testing, approval and installation of software updates and security patches to close known vulnerabilities. According to the Ponemon Institute, 57% of all successful cyberattacks can be traced back to vulnerabilities for which a patch was already available.
How does patch management work?
An effective patch management process begins with a complete inventory of all IT assets: servers, workstations, network devices, IoT devices and software. Vulnerability scanners identify which systems contain vulnerabilities by comparing software versions against CVE databases. Each vulnerability is prioritised based on CVSS score, exploitability and business impact. Patches are first tested in an acceptance environment to check for unintended side effects. After approval, patches are rolled out to production with monitoring for issues.
Patch management challenges
The volume is overwhelming: hundreds of new patches are published monthly. Legacy systems and OT environments often cannot be patched without production interruption. Dependencies between systems make patching complex. Some patches cause compatibility issues. Not all vulnerabilities have patches: zero-days require temporary mitigations. Shadow IT and unknown assets miss patches because they fall outside the management process.
Impact on organisations
The average time between CVE publication and active exploitation is shrinking: attackers exploit critical vulnerabilities increasingly quickly, sometimes within 24 hours. Organisations that fail to patch promptly face elevated risk of ransomware, data breaches and compliance fines. NIS2 requires systematic vulnerability management. ISO 27001 requires a documented patch management process. PCI DSS mandates installing critical patches within 30 days. DORA sets comparable requirements for financial institutions.
Protection
Implement an automated patch management platform for consistent and timely patching. Prioritise patches based on risk, not just CVSS score. Combine patch management with vulnerability scanning for a complete picture. Define emergency procedures for critical zero-day patches. Document exceptions and mitigating measures for systems that cannot be immediately patched.
How DEFION helps
DEFION provides Continuous Vulnerability Management supporting patch management with continuous scanning, risk-based prioritisation and concrete recommendations. The service identifies which vulnerabilities pose the highest risk and assists in structuring the patching process.