Three recent incidents expose fundamental gaps in UK business security practice. AOMEI Backupper, backup software deployed across millions of systems, suffered a supply chain compromise between April and July 2026 when attackers tampered with update infrastructure during brief windows, delivering remote access backdoors to users who triggered legitimate update checks. Citrix NetScaler devices face active exploitation of CVE-2026-88771, a critical remote code execution vulnerability with no workaround, as attackers deploy web shells and chain additional vulnerabilities for persistent access. The ICO has issued reprimands to two Welsh organisations following a ransomware breach affecting 3,300 people, predominantly children, after attackers gained entry through a forgotten test account secured with the password Password1. Additional reporting covers the compromise of a Microsoft 365 API credential belonging to ConnectWise Cloud Backup, which enabled automated bulk access across hundreds of customer tenants. The briefing provides actionable guidance for checking AOMEI exposure, confirming NetScaler patch status, auditing dormant accounts, and interrogating MSP access logging. None of these failures required sophisticated attack techniques. All map to existing NCSC guidance that remains unimplemented across UK SMB environments.