Fortinet · Multiple Products
CVE-2026-24858
Fortinet Multiple Products Authentication Bypass Using an Alternate Path or Channel Vulnerability
CISA KEV record
- CISA date added
- 2026-01-27
- CISA due date
- 2026-01-30
- Known ransomware use
- Unknown
NVD risk context
9.8 CRITICAL
CVSS is a technical severity score. CISA’s KEV status remains the evidence that this vulnerability is known to be exploited.
Description
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.
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.
NVD reference index
Vendor and remediation references
NVD has tagged these sources as vendor advisories, patches, mitigations, or release notes.
MITRE CWE context
CWE classification
The product requires authentication, but the product has an alternate path or channel that does not require authentication.
View official MITRE CWE details ↗NVD record timing
NVD record timeline
These dates describe NVD’s record, not CISA’s KEV addition or remediation due date.
- NVD published
- Jan 27, 2026, 08:16 PM UTC When NVD first published this CVE record.
- NVD last updated
- Jun 17, 2026, 10:23 AM UTC When NVD last changed its analysis or record data.
Advanced: view the technical CVSS vector
This standardized code is intended for security tools and technical analysts. The plain-language risk summary above explains its main points.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA notes
Please adhere to Fortinet's guidelines to assess exposure and mitigate risks. Check for signs of potential compromise on all internet accessible Fortinet products affected by this vulnerability. Apply any final mitigations provided by the vendor as soon as they become available. For more information please see: https://fortiguard.fortinet.com/psirt/FG-IR-26-060 ; https://www.fortinet.com/blog/psirt-blogs/analysis-of-sso-abuse-on-fortios ; https://nvd.nist.gov/vuln/detail/CVE-2026-24858