The authentication bypass vulnerabilities, CVE-2025-59718 and CVE-2025-59719, are in the Fortinet FortiOS operating system that runs FortiWeb, FortiProxy and FortiSwitchManager devices. If exploited, they may allow an unauthenticated attacker to bypass the FortiCloud SSO login authentication, if that feature is enabled on the device.
For some admins, it may have been unknowingly turned on; when administrators register devices usingthe FortiCareproduct support portal, FortiCloudSSO is automatically enabled unless they disable the “Allow administrative login usingFortiCloudSSO” setting on the registration page.
To prevent being affected by this vulnerability, admins should turn off the FortiCloud login feature, if enabled, then upgrade software to the latest version before re-enabling the function.
