FG-IR-25-647: Multiple Fortinet Products' FortiCloud SSO Login Authentication Bypass

Published Dec 9, 2025
·
Updated

An Improper Verification of Cryptographic Signature vulnerability[CWE-347] in FortiOS, FortiWeb, FortiProxy and FortiSwitchManager mayallow an unauthenticated attacker to bypass the FortiCloud SSO loginauthentication via a crafted SAML message, if that feature is enabled on the device. Please note that the FortiCloud SSO login feature is not enabled in default factory settings. However, when an administrator registers the device to FortiCare from the device's GUI, unless the administrator disables the toggle switch "Allow administrative login using FortiCloud SSO" in the registration page, FortiCloud SSO login is enabled upon registration. To prevent being affected by this vulnerability on vulnerableversions, please turn off the FortiCloud login feature (if enabled) temporarily untilupgrading to a non-affected version.To turn off FortiCloud login, go to System -> Settings -> Switch"Allow administrative login using FortiCloud SSO" to Off. Or type thefollowing command in the CLI: config system global set admin-forticloud-sso-login disableend

Affected Software

13 affected componentsFixes available
Fortinet FortiOS>=7.6.0<=7.6.3
Fortinet FortiOS>=7.4.0<=7.4.8
Fortinet FortiOS>=7.2.0<=7.2.11
Fortinet FortiOS>=7.0.0<=7.0.17
Fortinet FortiProxy>=7.6.0<=7.6.3
Fortinet FortiProxy>=7.4.0<=7.4.10
Fortinet FortiProxy>=7.2.0<=7.2.14
Fortinet FortiProxy>=7.0.0<=7.0.21
Fortinet FortiSwitchManager>=7.2.0<=7.2.6
Fortinet FortiSwitchManager>=7.0.0<=7.0.5
Fortinet FortiWeb=.
Fortinet FortiWeb>=7.6.0<=7.6.4
Fortinet FortiWeb>=7.4.0<=7.4.9

Event History

Dec 9, 2025
Advisory Published
via FortiGuard·12:00 AM
Data Sourced
via FortiGuard·12:00 AM
DescriptionSeverityWeaknessAffected Software
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of FG-IR-25-647?

The severity of FG-IR-25-647 is high due to its potential to allow unauthenticated access via a crafted SAML message.

2

How do I fix FG-IR-25-647?

To fix FG-IR-25-647, upgrade to the appropriate patched version of FortiOS, FortiWeb, FortiProxy or FortiSwitchManager as specified in the advisory.

3

Which versions of Fortinet products are affected by FG-IR-25-647?

FG-IR-25-647 affects multiple versions of FortiOS, FortiWeb, FortiProxy, and FortiSwitchManager, specifically those before the remedial versions listed in the advisory.

4

Can FG-IR-25-647 be exploited remotely?

Yes, FG-IR-25-647 can be exploited remotely by an unauthenticated attacker to bypass authentication.

5

What impacts does FG-IR-25-647 have on Fortinet devices?

FG-IR-25-647 allows an attacker to bypass the FortiCloud SSO login authentication, potentially leading to unauthorized access.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203