Fortinet Multiple Products Authentication Bypass Using an Alternate Path or Channel
What to do
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA deadline 2026-01-30 · passed 7 months ago · applies to US federal civilian agencies; used elsewhere as a reference SLA
What happened
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.
Who is affected
Fortinet Multiple Products. Affected version ranges are listed in the vendor advisory and the NVD entry linked under Sources.
Weakness class: CWE-288.
Timeline
- Added to CISA KEVExploitation in the wild confirmed by CISA
- CISA remediation deadlinepassed 7 months ago
Sources
- NVD entry for CVE-2026-24858 nvd.nist.gov/vuln/detail/CVE-2026-24858
- CISA Known Exploited Vulnerabilities catalog www.cisa.gov/known-exploited-vulnerabilities-catalog
- fortiguard.fortinet.com fortiguard.fortinet.com/psirt/FG-IR-26-060
- fortinet.com www.fortinet.com/blog/psirt-blogs/analysis-of-sso-abuse-on-fortios
- nvd.nist.gov nvd.nist.gov/vuln/detail/CVE-2026-24858