CVE-2026-41089: exploitation status and patch state

CVE-2026-41089 · CVSS 9.8 CRITICAL · EPSS 80% · patch available

Stack-based buffer overflow in Windows Netlogon allows an unauthorized attacker to execute code over a network.

Is CVE-2026-41089 exploited?

• Not in the CISA KEV catalog.
• EPSS puts exploitation in the next 30 days at 80%.
• Public exploit code: none found in monitored sources.

Which products and versions are affected?

• Microsoft · Windows Server 2012 · >= 6.2.9200.0, < 6.2.9200.26079
• Microsoft · Windows Server 2012 (Server Core installation) · >= 6.2.9200.0, < 6.2.9200.26079
• Microsoft · Windows Server 2012 R2 · >= 6.3.9600.0, < 6.3.9600.23181
• Microsoft · Windows Server 2012 R2 (Server Core installation) · >= 6.3.9600.0, < 6.3.9600.23181
• Microsoft · Windows Server 2016 · >= 10.0.14393.0, < 10.0.14393.9140
• Microsoft · Windows Server 2016 (Server Core installation) · >= 10.0.14393.0, < 10.0.14393.9140
• Microsoft · Windows Server 2019 · >= 10.0.17763.0, < 10.0.17763.8755
• Microsoft · Windows Server 2019 (Server Core installation) · >= 10.0.17763.0, < 10.0.17763.8755
• Microsoft · Windows Server 2022 · >= 10.0.20348.0, < 10.0.20348.5139
• Microsoft · Windows Server 2022, 23H2 Edition (Server Core installation) · >= 10.0.25398.0, < 10.0.25398.2330
• Microsoft · Windows Server 2025 · >= 10.0.26100.0, < 10.0.26100.32860
• Microsoft · Windows Server 2025 (Server Core installation) · >= 10.0.26100.0, < 10.0.26100.32860
• Microsoft · Windows Server 2022 (Server Core installation)

Is there a patch?

Yes. Update to one of these or later:

From Microsoft's CVE record · Microsoft advisory

• KB5087538
• KB5087545
• KB5087424
• KB5087539
• KB5087423
• KB5087541
• KB5087537
• KB5087470
• KB5087471

From Microsoft's Security Update Guide · Microsoft advisory

What PlainSec published about CVE-2026-41089

• Netlogon exploit puts Active Directory at risk (2026-06-11)

Primary sources

• NVD record
• Microsoft KB5087538
• Microsoft KB5087545
• Microsoft KB5087424
• Microsoft KB5087539
• Microsoft KB5087423
• Microsoft KB5087541
• Microsoft KB5087537
• Microsoft KB5087470
• Microsoft KB5087471

KEV and EPSS are re-checked daily. Record last updated 2026-10-25.