Risk Letters

Exploited vulnerability

CVE-2026-24858

TLP:CLEAR

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.

Facts

  • Vendor: Fortinet
  • Product: Multiple Products
  • CVSS: 9.8
  • EPSS (probability of exploitation within 30 days): 86.6 %
  • On CISA's Known Exploited Vulnerabilities list since: 27 January 2026
  • First known exploitation: 27 January 2026
  • CISA's deadline for US federal agencies: 30 January 2026
  • Weakness: CWE-288
  • First seen by Risk Letters: 27 January 2026

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Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD