High 8.8
KEV-listed
CVE-2026-21510
APT28 Exploitation of Microsoft Windows Shell Zero-Day Flaws CVE-2026-21510 and CVE-2026-32202
Vendor / product: Microsoft Windows Shell
Event date: 2025-12-01
Public PoC: Yes
First tracked by RiskWire: 2026-10-20
CISA KEV catalog
Added to KEV
Federal remediation due
2026-03-03 (231 days overdue)
Ransomware campaign use
Unknown
CISA description
Microsoft Windows Shell contains a protection mechanism failure vulnerability that could allow an unauthorized attacker to bypass a security feature over a network.
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Named threat actors
APT28
Sources & citations (7)
- AI加速漏洞研究，安全补丁失效案例增多 mezha.net · 2026-10-19
- Security patches need patches now that attackers have AI theregister.com · 2026-10-19
- Los parches de seguridad fallan más en 2026 y reavivan las alertas sobre la IA diariobitcoin.com · 2026-10-19
- Les échecs des correctifs de sécurité se multiplient à mesure que l'IA accélère la recherche de vulnérabilités mezha.net · 2026-10-19
- Security patch failures rise as AI accelerates vulnerability research mezha.net · 2026-10-19
- AI가 취약점 연구를 가속하면서 보안 패치 실패 증가 mezha.net · 2026-10-19
- AIによる脆弱性調査の加速で、セキュリティパッチの不具合が増加 mezha.net · 2026-10-19
References
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