CVE-2025-59718: Technical Deep-Dive (Auto Refreshed)

Generated on 2026-03-23T21:39:44.663Z. This file is automatically regenerated every 30 minutes by the CVE AI enrichment job using web sources (NVD, MITRE, CISA KEV, GitHub).

Executive Technical Summary

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.

• Context preserved from previous revision: 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. Notes: TK-CVE-Repo

Technical Details

• CVE: CVE-2025-59718
• KEV date added: 2025-12-16
• KEV due date: 2025-12-23
• NVD published: 2025-12-09
• NVD modified: 2025-12-17
• MITRE modified: 2026-03-20
• CVSS base score: 9.8
• CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
• CVSS exploitability score: 3.9
• CVSS impact score: 5.9
• Attack vector: Network
• Attack complexity: Low
• Privileges required: None
• User interaction: None
• Scope: Unchanged
• Confidentiality impact: High
• Integrity impact: High
• Availability impact: High

Versions and Products Impacted

• fortinet / fortiproxy (versions: >= 7.0.0, < 7.0.22)
• fortinet / fortiproxy (versions: >= 7.2.0, < 7.2.15)
• fortinet / fortiproxy (versions: >= 7.4.0, < 7.4.11)
• fortinet / fortiproxy (versions: >= 7.6.0, < 7.6.4)
• fortinet / fortiswitchmanager (versions: >= 7.0.0, < 7.0.6)
• fortinet / fortiswitchmanager (versions: >= 7.2.0, < 7.2.7)
• fortinet / fortios (versions: >= 7.0.0, < 7.0.18)
• fortinet / fortios (versions: >= 7.2.0, < 7.2.12)
• fortinet / fortios (versions: >= 7.4.0, < 7.4.9)
• fortinet / fortios (versions: >= 7.6.0, < 7.6.4)
• Fortinet / FortiSwitchManager (versions: 7.2.0, 7.0.0)
• Fortinet / FortiOS (versions: 7.6.0, 7.4.0, 7.2.0, 7.0.0)
• Fortinet / FortiProxy (versions: 7.6.0, 7.4.0, 7.2.0, 7.0.0)

Weakness Classification

• CWE-347

Repositories for Lab Validation (Public Examples)

• DarkFunct/TK-CVE-Repo | stars: 43 | updated: 2026-03-23 | https://github.com/DarkFunct/TK-CVE-Repo
  Notes: TK-CVE-Repo
• exfil0/CVE-2025-59718-PoC | stars: 5 | updated: 2026-02-18 | https://github.com/exfil0/CVE-2025-59718-PoC
  Notes: Fortinet announced two closely related authentication‑bypass vulnerabilities on 9 December 2025. Both flaws involve improper verification of cryptographic signatures (CWE‑347) in the handling of SAML responses for the FortiCloud SSO login feature.
• moften/CVE-2025-59718-Fortinet-Poc | stars: 3 | updated: 2026-03-19 | https://github.com/moften/CVE-2025-59718-Fortinet-Poc
  Notes: PoC para determinar si Fortinet es vulnerable a CVE-2025-59718 / CVE-2025-59719
• barkandbite/iranian-apt-detection | stars: 1 | updated: 2026-03-12 | https://github.com/barkandbite/iranian-apt-detection

People and Organizations Mentioned

• fortinet
• Multiple Products
• DarkFunct
• exfil0
• moften
• barkandbite

Practical Defensive Validation (Authorized Only)

1. Use only isolated environments and systems you own or are explicitly authorized to test.
2. Snapshot infrastructure before validation and preserve baseline logs (EDR, SIEM, OS, app).
3. Inventory fortinet / fortiproxy (versions: >= 7.0.0, < 7.0.22) assets and confirm exact vulnerable versions with automated checks.
4. Patch in staged environments and validate closure with scanners + service health checks.
5. Map detections to MITRE ATT&CK tactics relevant to your environment and tune alert quality.

References

• NVD record: https://nvd.nist.gov/vuln/detail/CVE-2025-59718
• MITRE CVE record: https://www.cve.org/CVERecord?id=CVE-2025-59718
• CISA KEV Catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• CISA KEV JSON feed: https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json
• KEV 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
• https://fortiguard.fortinet.com/psirt/FG-IR-25-647
• https://arcticwolf.com/resources/blog/arctic-wolf-observes-malicious-sso-logins-following-disclosure-cve-2025-59718-cve-2025-59719/
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-59718
• Repository example: https://github.com/DarkFunct/TK-CVE-Repo
• Repository example: https://github.com/exfil0/CVE-2025-59718-PoC
• Repository example: https://github.com/moften/CVE-2025-59718-Fortinet-Poc
• Repository example: https://github.com/barkandbite/iranian-apt-detection

This content is for defensive security training and authorized validation only.