What is CVE-2026-33843?

CVE-2026-33843 is a critical-severity vulnerability in Microsoft Entra Id, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.1/10. Published 2026-05-22.

How severe is CVE-2026-33843?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Vulnerability in Microsoft Entra Id

CVE-2026-33843

Authentication bypass using an alternate path or channel in Microsoft Azure Active Directory B2C allows an unauthorized attacker to elevate privileges over a network.

Published 2026-05-22 · last modified 2026-07-23.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.009 (58.3th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 58.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-288 — Authentication Bypass Using an Alternate Path or Channel

References

Microsoft Azure Active Directory B2C Elevation of Privilege Vulnerability (vendor-advisory, patch, Vendor Advisory)

Frequently asked questions

What is CVE-2026-33843?: CVE-2026-33843 is a critical-severity vulnerability in Microsoft Entra Id, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.1/10. Published 2026-05-22.
How severe is CVE-2026-33843?: Critical severity. CVSS v3 base score is 9.1 out of 10.