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

CVE-2025-59718 is rated critical with a CVSS v3.1 base score of 9.8 and affects Fortinet Multiple Products, along with 1 other product in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2025-12-16, which means exploitation in the wild has been observed.

Vulnerability description

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.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-347: Improper Verification of Cryptographic Signature

The product does not verify, or incorrectly verifies, the cryptographic signature for data.

Affected products

  • Fortinet Fortiproxy: from 7.0.0 before 7.0.22; from 7.2.0 before 7.2.15; from 7.4.0 before 7.4.11; from 7.6.0 before 7.6.4
  • Fortinet Fortiswitchmanager: from 7.0.0 before 7.0.6; from 7.2.0 before 7.2.7
  • Fortinet Fortios: from 7.0.0 before 7.0.18; from 7.2.0 before 7.2.12; from 7.4.0 before 7.4.9; from 7.6.0 before 7.6.4
  • Siemens Ruggedcom Ape1808 Firmware: all versions listed by NVD

References