⚠ Reference material — not professional advice. Test in staging, back up first, verify against your specific version. Use your own judgment for your environment.
● Critical · CVSS 9.1 ⚠ ACTIVELY EXPLOITED — CISA KEV

How to Fix CVE-2025-59718: Access Control Bypass in FortiSwitchManager

Other vulnerabilities in the same area that are worth patching alongside this one:

*By Sai Kiran Pandrala*

⚡ At a glance
SeverityCVSS 9.1 - Critical
Actively exploited?Yes, listed in CISA KEV (added 2025-12-16)
Affected7.2.0 <= 7.2.6, 7.0.0 <= 7.0.5, 7.6.0 <= 7.6.3, 7.4.0 <= 7.4.8, 7.2.0 <= 7.2.11, 7.0.0 <= 7.0.17, and others
Fixed inSee vendor advisory
Type (CWE)CWE-347: Improper access control
Patch immediately. CISA's KEV listing means active exploitation is confirmed. Federal agencies must remediate by 2025-12-23.

What is CVE-2025-59718?

CVE-2025-59718 is an access control bypass flaw in FortiSwitchManager. Authenticated or in some cases unauthenticated requests reach endpoints they should not be allowed to call, exposing administrative functionality or sensitive data. Vendor 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.

Why this CVE matters

Access control flaws let an attacker reach endpoints the developers assumed would be reserved for administrators. The impact depends on what those endpoints expose, but for management products the answer is usually configuration changes, log access, or credential reads.

For deployments of FortiSwitchManager that have been exposed to the public internet during the disclosure window, the operating assumption should be that scanning has already happened. Confirmed in-the-wild exploitation makes that assumption mandatory, not cautious. Patching closes the door; log review and credential rotation close out the rest of the response.

Am I affected?

You are affected if your installation matches any of these version ranges:

Check your installed version against the list above. If you cannot determine the version, treat the system as affected and follow the upgrade path below.

On FortiGate / FortiOS systems, run get system status from the CLI and compare the Version line against the affected ranges above.

How to fix CVE-2025-59718

  1. Read the vendor advisory in full: https://fortiguard.fortinet.com/psirt/FG-IR-25-647
  2. Upgrade FortiSwitchManager to the patched build listed in the vendor advisory.
  3. Back up the configuration (and database, where applicable) before upgrading.
  4. Apply the patch in a maintenance window. For HA pairs, upgrade the standby node first, fail over, then upgrade the former primary.
  5. Restart the affected service so the patched binary loads, then verify the new version (see verification section).

Apply the iOS / iPadOS update


# Check the current iOS build on a tethered device (libimobiledevice)
ideviceinfo -k ProductVersion
ideviceinfo -k BuildVersion

# Required iOS / iPadOS build is listed in the vendor advisory: https://fortiguard.fortinet.com/psirt/FG-IR-25-647
# On-device: Settings -> General -> Software Update -> Download and Install


# Vendor advisory: https://fortiguard.fortinet.com/psirt/FG-IR-25-647
# Confirm fleet iOS devices have updated (Intune example)
Connect-MgGraph -Scopes Device.Read.All
Get-MgDeviceManagementManagedDevice -Filter "operatingSystem eq 'iOS'" |
  Where-Object { $_.OSVersion -lt "<fixed-version-from-advisory>" } |
  Select-Object DeviceName, OSVersion, UserPrincipalName

Verify the fix landed


# 1. Confirm the running version matches the fixed-in version from the advisory:
#    https://fortiguard.fortinet.com/psirt/FG-IR-25-647
#    Use the platform-specific version probe above.

# 2. Re-scan with your vulnerability scanner (Nessus, Qualys, Tenable, OpenVAS).
#    The scanner should no longer flag CVE-2025-59718 on the patched target.

# 3. Inspect recent service / kernel logs for crash loops or rollback events.
journalctl -u <service> --since "10 minutes ago"
dmesg --since "10 minutes ago"

If you cannot patch immediately

No official workaround exists beyond restricting network exposure to the affected component. Apply the vendor patch as the primary remediation.

How to verify the fix worked

If your installation was internet-reachable during the disclosure window, treat log review as part of the remediation rather than an optional follow-up. Look for log entries that do not match your normal request patterns, especially repeated requests to the same uncommon endpoint, and any administrative changes you cannot tie back to a known operator. Because FortiSwitchManager sits on CISA's Known Exploited Vulnerabilities catalog for this CVE, defenders should also pull the IOC list from the vendor advisory and from CISA's analysis if one was published.

Frequently asked questions

Is CVE-2025-59718 being exploited in the wild?

Yes. CISA added CVE-2025-59718 to the Known Exploited Vulnerabilities catalog, which means active exploitation has been confirmed by federal observation or credible vendor reporting.

Will a WAF or IDS rule fully mitigate CVE-2025-59718?

No. Network-layer filters can reduce noise and slow opportunistic scanners, but they will not stop a determined attacker. The vendor patch is the only durable fix.

How long should I plan for the upgrade?

Typical vendor-documented upgrade windows for FortiSwitchManager run from a few minutes to under an hour depending on cluster size. Test in a staging environment first and follow the vendor's documented HA upgrade order.

References

*This guide was assembled from the official vendor advisory, the NVD record, and the CISA KEV catalog entry on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*