FortiOS
CVE-2025-59718: Improper verification of cryptographic signature in FortiOS, FortiProxy and others
A improper verification of cryptographic signature vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2.0 through 7.2.11, FortiOS 7.0.0 through 7.0.17, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4.0 through 7.4.10, FortiProxy 7.2.0 through 7.2.14, FortiProxy 7.0.0 through 7.0.21, FortiSwitchManager 7.2.0 through 7.2.6, FortiSwitchManager 7.0.0 through 7.0.5 allows an unauthenticated attacker to bypass the FortiCloud SSO login authentication via a crafted SAML response message.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| FortiSwitchManager 7.2.0 to 7.2.6 | 7.2.7 or later |
| FortiSwitchManager 7.0.0 to 7.0.5 | 7.0.6 or later |
| FortiOS 7.6.0 to 7.6.3 | 7.6.4 or later |
| FortiOS 7.4.0 to 7.4.8 | 7.4.9 or later |
| FortiOS 7.2.0 to 7.2.11 | 7.2.12 or later |
| FortiOS 7.0.0 to 7.0.17 | 7.0.18 or later |
| FortiProxy 7.6.0 to 7.6.3 | 7.6.4 or later |
| FortiProxy 7.4.0 to 7.4.10 | 7.4.11 or later |
| FortiProxy 7.2.0 to 7.2.14 | 7.2.15 or later |
| FortiProxy 7.0.0 to 7.0.21 | 7.0.22 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
A improper verification of cryptographic signature vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2.0 through 7.2.11, FortiOS 7.0.0 through 7.0.17, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4.0 through 7.4.10, FortiProxy 7.2.0 through 7.2.14, FortiProxy 7.0.0 through 7.0.21, FortiSwitchManager 7.2.0 through 7.2.6, FortiSwitchManager 7.0.0 through 7.0.5 allows an unauthenticated attacker to bypass the FortiCloud SSO login authentication via a crafted SAML response message.
Exploitation
CISA lists this CVE as exploited in the wild since 16 Dec 2025.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 10 Oct 2026.