CVE-2026-24858 Fortinet Multiple Products Authentication Bypass Using an Alternate Path or Channel Vulnerability
Fortinet FortiAnalyzer, FortiManager, FortiOS, and FortiProxy contain an authentication bypass using an alternate path or channel that could allow an attacker with a FortiCloud account and a registered device to log into other devices registered to other accounts, if FortiCloud SSO authentication is enabled on those devices.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 27 Jan 2026.
- Rated Critical severity (CVSS 9.4, scored by Vendor).
- It has been in the catalogue for 283 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] vulnerability in Fortinet FortiAnalyzer 7.6.0 through 7.6.5, FortiAnalyzer 7.4.0 through 7.4.9, FortiAnalyzer 7.2.0 through 7.2.11, FortiAnalyzer 7.0.0 through 7.0.15, FortiManager 7.6.0 through 7.6.5, FortiManager 7.4.0 through 7.4.9, FortiManager 7.2.0 through 7.2.11, FortiManager 7.0.0 through 7.0.15, FortiNAC-F 7.6.3 through 7.6.5, FortiOS 7.6.0 through 7.6.5, FortiOS 7.4.0 through 7.4.10, FortiOS 7.2.0 through 7.2.12, FortiOS 7.0.0 through 7.0.18, FortiProxy 7.6.0 through 7.6.4, FortiProxy 7.4.0 through 7.4.12, FortiProxy 7.2.0 through 7.2.15, FortiProxy 7.0.0 through 7.0.22, FortiWeb 8.0.0 through 8.0.3, FortiWeb 7.6.0 through 7.6.6, FortiWeb 7.4.0 through 7.4.11 may allow an attacker with a FortiCloud account and a registered device to log into other devices registered to other accounts, if FortiCloud SSO authentication is enabled on those devices.
Affected Versions
| Product | Versions |
|---|---|
| Fortinet FortiWeb | 8.0.0 to 8.0.3 7.6.0 to 7.6.6 7.4.0 to 7.4.11 |
| Fortinet FortiNAC-F | 7.6.3 to 7.6.5 |
| Fortinet FortiOS | 7.6.0 to 7.6.5 7.4.0 to 7.4.10 7.2.0 to 7.2.12 7.0.0 to 7.0.18 |
| Fortinet FortiAnalyzer | 7.6.0 to 7.6.5 7.4.0 to 7.4.9 7.2.0 to 7.2.11 7.0.0 to 7.0.15 |
| Fortinet FortiProxy | 7.6.0 to 7.6.4 7.4.0 to 7.4.12 7.2.0 to 7.2.15 7.0.0 to 7.0.22 |
| Fortinet FortiManager | 7.6.0 to 7.6.5 7.4.0 to 7.4.9 7.2.0 to 7.2.11 7.0.0 to 7.0.15 |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Fortinet Multiple Products. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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