Use after free in Windows Failover Cluster allows an unauthorized attacker to execute code over a network.
Fix
Microsoft's update · Important
- KB5126651 — Windows Server 2019, Windows Server 2019 (Server Core installation) · build 10.0.17763.9376 · restart required
- KB5126655 — Windows Server 2022, Windows Server 2022 (Server Core installation) · build 10.0.20348.5761 · restart required
- KB5126646 — Windows Server 2025, Windows Server 2025 (Server Core installation) · build 10.0.26100.33650 · restart required
From the 2026-Oct release note of Microsoft's Security Update Guide, revised 2026-10-28 · Exploitation Unlikely.
Patch, vendor advisory and mitigation references on NVD 1
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88102 Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 3
- Cpes+3 CPE criteria (now 3)NVD modified 2026-10-16 15:42
- StatusUndergoing Analysis → AnalyzedNVD modified 2026-10-16 15:42
- First seenCVSS 9.8NVD modified 2026-10-14 04:18
Affected (CPE criteria) 3
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:x64:*cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:x64:*cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:*
References 1
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88102 Patch, Vendor Advisory