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Windows Netlogon stack-based buffer overflow security flaw (CVE-2026-41089)

Vulnerability
First reported
Last updated
Happening score
H score 37
2 unique sources, 2 articles

Summary

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Microsoft’s May Patch Tuesday fixed CVE-2026-41089, a critical stack-based buffer overflow in Windows Netlogon that could let attackers gain system privileges on a domain controller. The flaw has a CVSS v3 score of 9.8, requires no privileges or user interaction, and is rated low complexity. Security teams responsible for domain controllers should prioritize remediation.

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How related: "On Friday, Belgium's national cybersecurity authority (CCB) warned that attackers are now actively exploiting the CVE-2026-41089 security flaw in the wild and urged admins to immediately patch vulnerable servers."

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Timeline

  1. 13.05.2026 11:15 3 articles · 1mo ago

    Microsoft fixes CVE-2026-41089 in Windows Netlogon

    Initial Disclosure

    Microsoft published May Patch Tuesday security updates that fixed 120 CVEs, including CVE-2026-41089 in Windows Netlogon, a critical stack-based buffer overflow with a CVSS v3 base score of 9.8 that could give attackers system privileges on a domain controller. Rapid7 principal software engineer Adam Barnett urged anyone responsible for securing a domain controller to prioritize remediation, noting that no privileges or user interaction are required and attack complexity is low.

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