CVE-2026-21509
CISA KEV Active Alert
Reliance on untrusted inputs in a security decision in Microsoft Office allows an unauthorized attacker to bypass a security feature locally.
Attack Parameters
Technical Impact
Affected Configurations
Total: 5 detected entries
Time Line
Key Metrics
Recommended Solution
Related News Articles
2 article(s) mentioning this vulnerability
Microsoft publie un correctif urgent pour une vulnérabilité zero-day dans Microsoft Office
Microsoft a publié un correctif urgent pour une vulnérabilité zero-day dans Microsoft Office, impactant la sécurité des fonctionnalités. Cisco Talos…
Microsoft Releases Critical Update to Patch Zero-Day Vulnerability in Microsoft Office
Microsoft has released an OOB update to address a critical zero-day vulnerability (CVE-2026-21509) in Microsoft Office, impacting security feature bypass.…
Immediate Action Plan
1. Inventory
Identify all affected systems in your infrastructure.
2. Assessment
Assess exposure and criticality for your organization.
3. Mitigation
Apply patches or available workarounds.
4. Verification
Test and confirm effectiveness of applied measures.
⚠️ MAXIMUM PRIORITY - Immediate action required