Introduction
Privilege escalation in cloud eventing systems can disrupt automated workflows and expose sensitive data. CVE-2025-59273 is a high-severity improper access control vulnerability in Microsoft Azure Event Grid, published on October 23, 2025. This brief summary highlights the available technical information, affected systems, and vendor security context relevant to security professionals.
Azure Event Grid is a core eventing service within Microsoft Azure, enabling scalable event-driven architectures for enterprises worldwide. Microsoft Azure is one of the largest cloud platforms globally, serving millions of organizations and integrating deeply with Microsoft 365 and Windows environments.
Technical Information
CVE-2025-59273 is classified under CWE-284 (improper access control). The vulnerability allows an unauthorized attacker to escalate privileges over a network. The CVSS v3.1 vector is:
AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
- Attack Vector: Network
- Attack Complexity: Low
- Privileges Required: None
- User Interaction: None
- Scope: Unchanged
- Confidentiality Impact: Low
- Integrity Impact: Low
- Availability Impact: Low
The vulnerability affects the Azure Event Grid system. No further technical details, exploitation methods, or vulnerable code snippets are publicly available as of the publication date.
Affected Systems and Versions
- Product: Microsoft Azure Event Grid
- Affected: Azure Event Grid System (no further version or configuration details are available in public sources)
Vendor Security History
Microsoft Azure has experienced several high-severity vulnerabilities in 2025, including privilege escalation issues in Entra ID (CVE-2025-55241) and Compute Gallery (CVE-2025-59291, CVE-2025-59292). Microsoft typically responds quickly to critical vulnerabilities, but the recurrence of access control issues in Azure services highlights ongoing challenges in cloud security.
