What is CVE-2026-62873?

CVE-2026-62873 is a critical-severity vulnerability in Microsoft 365 Admin Center, classified under Improper Verification of Cryptographic Signature. CVSS score: 9.8/10. Published 2026-08-07.

How severe is CVE-2026-62873?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Microsoft 365 Admin Center

CVE-2026-62873

Improper verification of cryptographic signature in Microsoft 365 Admin Center allows an unauthorized attacker to elevate privileges over a network.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft 365 Admin Center
Microsoft Windows_admin_center

Weakness classification (CWE)

CWE-347 — Improper Verification of Cryptographic Signature

References

secure@microsoft.com (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-62873?: CVE-2026-62873 is a critical-severity vulnerability in Microsoft 365 Admin Center, classified under Improper Verification of Cryptographic Signature. CVSS score: 9.8/10. Published 2026-08-07.
How severe is CVE-2026-62873?: Critical severity. CVSS v3 base score is 9.8 out of 10.