Microsoft Account vulnerabilities

3 CVEs affecting Microsoft Account, 0 known to be exploited (CISA KEV), with EPSS scores. Latest: CVE-2026-56165, published 2026-07-24.

More from Microsoft.

Highest priority

Known exploited (CISA KEV) first, then by EPSS exploit probability.

• CVE-2026-56165, published 2026-07-24. Critical severity, CVSS 9.8. EPSS: 1% chance of exploitation in the next 30 days. Heap-based buffer overflow in Microsoft Account allows an unauthorized attacker to execute code over a network.
• CVE-2025-21396, published 2025-01-29. High severity, CVSS 8.2. EPSS: 0.7% chance of exploitation in the next 30 days. Missing authorization in Microsoft Account allows an unauthorized attacker to elevate privileges over a network.
• CVE-2026-21264, published 2026-01-22. Medium severity, CVSS 6.1. EPSS: 0.4% chance of exploitation in the next 30 days. Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Account allows an unauthorized attacker to perform spoofing over a network.