How severe is CVE-2025-59718?

CVE-2025-59718 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-59718 being actively exploited?

Yes. CVE-2025-59718 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2025-12-16, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2025-59718?

CVE-2025-59718 primarily affects Fortinet Fortiproxy. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-59718?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2025-59718 have an EU (EUVD) identifier?

Yes. CVE-2025-59718 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-202198. It is also flagged as exploited in the EUVD (since 2025-12-16).

When was CVE-2025-59718 published?

CVE-2025-59718 was published on 2025-12-09 and last updated on 2026-06-17.

CVE-2025-59718

CVE-2025-59718 is a critical-severity vulnerability in Fortinet Fortiproxy with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2025-12-16). The underlying weakness is classified as CWE-347.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 66% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2025-12-16)
EU (EUVD) id: EUVD-2025-202198
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2025-12-16)
Weakness: CWE-347
Affected product: Fortinet Fortiproxy
Published: 2025-12-09
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-59718?: 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.
How severe is CVE-2025-59718?: CVE-2025-59718 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-59718 being actively exploited?: Yes. CVE-2025-59718 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2025-12-16, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2025-59718?: CVE-2025-59718 primarily affects Fortinet Fortiproxy. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-59718?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2025-59718 have an EU (EUVD) identifier?: Yes. CVE-2025-59718 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-202198. It is also flagged as exploited in the EUVD (since 2025-12-16).
When was CVE-2025-59718 published?: CVE-2025-59718 was published on 2025-12-09 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortiswitchmanager:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:ruggedcom_ape1808_firmware:-:*:*:*:*:*:*:*

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