M&A integration is the process of combining teams, systems, processes, and security controls after a merger or acquisition. In cyber security, it is one of the most sensitive phases of a deal because two organizations often bring different identity systems, approval workflows, endpoints, cloud services, and monitoring tools. If those environments are merged poorly, gaps can appear in access control, logging, patching, and incident response.
For defenders, strong M&A integration means mapping controls early, comparing user roles, decommissioning redundant systems, and deciding which standards will become the new baseline. It also requires budget and change management, because retraining staff and aligning procedures can be as important as replacing hardware. Attackers may exploit this transition by targeting temporary accounts, shared credentials, stale VPN access, or systems that were left in place during consolidation. Good integration reduces that exposure by making ownership clear and closing security drift before it becomes a breach path.