FortiCloud SSO Authentication Bypass Vulnerabilities Actively Exploited
Multiple critical authentication bypass vulnerabilities related to FortiCloud Single Sign-On (SSO) have been actively exploited in Fortinet products. CVE-2026-24858, disclosed in January 2026, allowed malicious actors with a FortiCloud account to log in to devices registered to other users if FortiCloud SSO was enabled. This led to unauthorized firewall configuration changes, account creation, and VPN configuration changes. Earlier, CVE-2025-59718 and CVE-2025-59719 (December 2025) allowed unauthenticated attackers to bypass SSO login via crafted SAML messages. Attacks exploiting these flaws have been observed creating rogue accounts and stealing firewall configuration data.
Signal context
First seen: Dec 10, 2025
Last updated: Jun 19, 2026
Status: Public signal
Key points
- CVE-2026-24858: Authentication bypass allowing unauthorized access to FortiOS, FortiManager, FortiWeb, FortiProxy, and FortiAnalyzer devices with FortiCloud SSO enabled.
- Exploitation led to unauthorized firewall configuration changes, account creation, and VPN configuration changes.
- CVE-2025-59718 and CVE-2025-59719: Improper verification of cryptographic signatures allowing SSO bypass via crafted SAML messages in FortiOS, FortiProxy, FortiSwitchManager, and FortiWeb.
Signal analysis
BetaIt helps compare this signal with other published signals without treating the labels as final determinations.
Likely country: Location not provided
Watch internet-facing systems, credential abuse and exploit activity.
- Source type: outside the affected organization
Impact area: Confidentiality
Likely asset: User or customer data
- 1 signal in the same sector
- 90 signals with the same likely impact area
- 1 signal linked to this organization/domain
External sources
https://www.bleepingcomputer.com/news/security/hackers-breach-fortinet-fortigate-devices-steal-firewall-configs/https://www.bleepingcomputer.com/news/security/hackers-breach-fortinet-fortigate-devices-steal-firewall-configs/Public source from bleepingcomputer.com.
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