Microsoft Exchange Server Zero-Day XSS Vulnerability Exploited in Active Attacks
Microsoft has disclosed a high-severity zero-day vulnerability in Exchange Server that is actively being exploited in the wild. The flaw enables threat actors to execute arbitrary code through cross-site scripting (XSS) attacks targeting Outlook on the web users. Microsoft has issued mitigations while a full patch is pending. The global reach of Exchange Server deployments makes this a significant cyber risk event affecting organisations worldwide.
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Impact verdict
Medium impact. MEDIUM: Admin recalibration. The event has a plausible London Market pathway, but the current evidence does not support HIGH: no confirmed market-moving insured loss, vessel total loss, major closure, quantified claims estimate, reinsurance trigger, or broad pricing/capacity response is evidenced.
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