CVE-2025-59718 — Fortinet Multiple Products Improper Verification of Cryptographic Signature Vulnerability
CVE-2025-59718: Fortinet Multiple Products Improper Verification of Cryptographic Signature Vulnerability
CISA Known Exploited Vulnerability (KEV)
| Vendor / project | Fortinet |
| Product | Multiple Products |
| Date added | 2025-12-16 |
| Due date | 2025-12-23 |
| Ransomware campaign use | Unknown |
Description
Fortinet FortiOS, FortiSwitchMaster, FortiProxy, and FortiWeb contain an improper verification of cryptographic signature vulnerability that may allow an unauthenticated attacker to bypass the FortiCloud SSO login authentication via a crafted SAML message. Please be aware that CVE-2025-59719 pertains to the same problem and is mentioned in the same vendor advisory. Ensure to apply all patches mentioned in the advisory.
Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Notes
https://fortiguard.fortinet.com/psirt/FG-IR-25-647 ; https://docs.fortinet.com/upgrade-tool/fortigate ; https://nvd.nist.gov/vuln/detail/CVE-2025-59718
References
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-59718
- KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog