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CVE-2026-83711: Microsoft Azure Active Directory B2c: Authentication bypass
CVE-2026-83711 is rated critical with a CVSS v3.1 base score of 10.0 and affects Microsoft Azure Active Directory B2c. Per its scoring, it can be exploited over the network, without authentication, without any user interaction.
Vulnerability description
Authorization bypass through user-controlled key in Microsoft Azure Active Directory B2C allows an unauthorized attacker to elevate privileges over a network.
Severity breakdown
CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
- Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
- Attack complexity: Low. No special conditions; the attack can be repeated reliably.
- Privileges required: None. No account or prior access is needed.
- User interaction: None. No action from any user is needed.
- Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
- Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
- Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
- Availability impact: None. No effect on availability.
Underlying weakness
CWE-639: Authorization Bypass Through User-Controlled Key
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
Affected products
- Microsoft Azure Active Directory B2c: all versions listed by NVD