SB2023062281 - Authentication bypass in Grafana Azure AD OAuth

Description

This security bulletin contains information about 1 security vulnerability.

1) Improper Authentication (CVE-ID: CVE-2023-3128)

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to an error in Azure AD OAuth implementation. Grafana is validating Azure AD accounts based on the email claim. On Azure AD, the profile email field is not unique and can be easily modified. A remote attacker can modify their profile and provide the email address of  an existing Grafana user, bypass authentication process and gain unauthorized access to the application.

The vulnerability affects Grafana installations with Azure AD OAuth configured for a multi-tenant app.

Remediation

Install update from vendor's website.

References

• https://github.com/grafana/grafana/releases/tag/v9.3.16
• https://github.com/grafana/grafana/releases/tag/v9.2.20
• https://grafana.com/security/security-advisories/cve-2023-3128/