CVE-2026-83711: Microsoft Azure Active Directory B2C Elevation of Privilege Vulnerability

criticalCVSS 10CVE-2026-83711

Authorization bypass through user-controlled key in Microsoft Azure Active Directory B2C allows an unauthorized attacker to elevate privileges over a network.

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: critical — CVSS 10
Published: 2026-09-08
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-83711

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-837110.58% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 46% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-83711	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

Recent advisories for Microsoft Azure Active

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

criticalCVE-2026-83711: Authorization bypass through user-controlled key in Microsoft Azure Active Directory B2C allow…nvd · 2026-09-03
unknownCVE-2026-54733: The Microsoft 365 and Microsoft Entra ID Plugins for Moodle provide Office 365 and Azure Activ…nvd · 2026-07-16