Actively exploited vulnerability

CVE-2025-59718: Fortinet Multiple Products Improper Verification of Cryptographic Signature Vulnerability

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.

CISA KEV source 16 Dec 2025 added 23 Dec 2025 remediation due

Affected product

Fortinet ยท Multiple Products

Known ransomware use: Unknown

Required action

Follow the source advisory and validate exposure in your environment.

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Related Yasna coverage

Recent reporting that mentions CVE-2025-59718.