Act nowDisclosed

Advisory · CVE-2026-45480

Azure AD improper authentication enables privilege escalation

An improper authentication flaw in Azure Active Directory lets an unauthorized attacker elevate privileges over the network, with a CVSS 10.0 rating.

Vendor
Microsoft
Product
Azure Active Directory
Identifier / CWE
CVE-2026-45480
CWE-287
Action timing
Immediate
ELI5

Explain it like I’m five

The bouncer at the identity system's front door has a flaw: at a certain side entrance, saying the right words gets you a VIP wristband with no ID check at all.

SIMPLIFIED_ATTACK_PATH04 STEPS
  1. 01Attacker connects

    An unauthorized attacker reaches the Azure Active Directory service over the network, with no credentials.

  2. 02Authentication flaw abused

    The attacker exploits the improper authentication weakness in the service.

  3. 03Privileges elevated

    The attacker gains elevated privileges within the identity plane.

  4. 04Identity fabric at risk

    Elevated identity privileges can be leveraged against applications, roles, and resources trusting the directory.

What happened

Microsoft published CVE-2026-45480, an improper authentication vulnerability (CWE-287) in Azure Active Directory, on June 18, 2026. The CVSS 3.1 vector (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H, score 10.0) indicates an unauthorized attacker can elevate privileges over the network with no privileges required and no user interaction, with scope changed. Microsoft has not published technical details of the flawed mechanism beyond this description, which is typical for managed Azure service advisories: the fix is applied in Microsoft’s infrastructure rather than shipped as a customer-deployable patch. There is no confirmed public exploitation at the time of writing.

What to do

  1. Review the MSRC advisory for CVE-2026-45480 and confirm your tenant’s exposure guidance from Microsoft.
  2. Audit privileged role assignments in Microsoft Entra ID (Global Administrator, Privileged Role Administrator, and application admin roles) and remove standing access that is not needed.
  3. Enforce least privilege and Conditional Access policies, including phishing-resistant MFA, on all privileged identities.
  4. Monitor sign-in logs and audit logs for anomalous role assignments, consent grants, and authentication anomalies around the disclosure window.

Management note

A 10.0 in the identity provider is the highest-leverage kind of cloud vulnerability: identity is the control plane everything else trusts. Even with sparse public detail, the correct posture is to shrink the blast radius now by cutting standing privilege and watching the identity logs, rather than waiting for a detailed exploit writeup.