Ransomware crews exploit Microsoft Defender BlueHammer privilege escalation
Source headline: CISA: Windows BlueHammer flaw now exploited by ransomware gangs
Intelligence Summary
CISA says ransomware operators are now using the Windows BlueHammer flaw to gain elevated privileges. The issue is tied to a Microsoft Defender privilege escalation vulnerability previously seen in zero-day activity. Exploitation can enable attackers to move from initial access to higher-impact actions on compromised systems. The risk is greater for organizations that run vulnerable Windows configurations without the relevant protections. Defenders should review CISA guidance, hunt for related activity, and ensure systems are updated and hardened.
Recommended Action
Inventory where Windows Defender runs in your environment and treat this as an active remediation item. Until then, watch authentication and outbound traffic logs for the indicators described in the source. This signal rests on a single report, so corroborate it before acting on anything irreversible.