{"api_version":"1","generated_at":"2026-07-23T14:45:26+00:00","cve":"CVE-2025-66390","urls":{"html":"https://cve.report/CVE-2025-66390","api":"https://cve.report/api/cve/CVE-2025-66390.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2025-66390","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-66390"},"summary":{"title":"CVE-2025-66390","description":"In Microsoft Azure API Management through 2025-10-17, when self-service signup (username/password Basic Authentication) is enabled in Tenant A, an attacker can reuse the registration flow by changing the hostname or tenant identifier to Tenant B, even when Tenant B has signup disabled at the UI level. In other words, disabling signup in the UI does not disable the underlying API endpoint (which still accepts cross-tenant requests based on the Host header). 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