Fortinet Multiple Products Improper Verification of Cryptographic Signature
CVE-2025-59718 is a critical-severity improper verification of cryptographic signature vulnerability in FortiSwitchManager from Fortinet, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected FortiSwitchManager versions: 7.2.0 through 7.2.6; 7.0.0 through 7.0.5. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on December 16, 2025, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Check which version of FortiSwitchManager you run against the affected versions below, and install the vendor's latest release.
- CISA's required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Read the advisory on fortiguard.fortinet.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Fortinet | FortiSwitchManager | 7.2.0 through 7.2.6; 7.0.0 through 7.0.5 | Not stated |
| Fortinet | FortiOS | 7.6.0 through 7.6.3; 7.4.0 through 7.4.8; 7.2.0 through 7.2.11; 7.0.0 through 7.0.17 | Not stated |
| Fortinet | FortiProxy | 7.6.0 through 7.6.3; 7.4.0 through 7.4.10; 7.2.0 through 7.2.14; 7.0.0 through 7.0.21 | Not stated |
| Siemens | RUGGEDCOM APE1808 | all versions | Not stated |
| Siemens | Ruggedcom Ape1808 Firmware | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (fortinet.com).
Official 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Verification of Cryptographic Signature
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
More Improper Verification of Cryptographic Signature vulnerabilities (CWE-347)
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
- Deadline for US federal agencies to remediate, set by CISA.
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- arcticwolf.com/resources/blog/arctic-wolf-observes-malicious-sso-logins-following-disclosure-cve-2025-59718-c…Third Party Advisory
- cert-portal.siemens.com/productcert/html/ssa-864900.htmlThird Party Advisory
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-59718US Government Resource
Other vulnerabilities in FortiSwitchManager
- 6.5 Medium severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.2 High severity
- 8.1 High severity
- 7.2 High severity
Recent Improper Verification of Cryptographic Signature vulnerabilities
- 9.8 Critical severity
- 9.1 Critical severity
- 9.1 Critical severity
- 7.8 High severity
- 7.5 High severity
- 9.3 Critical severity
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