FortiGate FortiCloud SSO Login from Unusual Source
This rule detects the first successful FortiCloud SSO login from a previously unseen source IP address to a FortiGate device within the last 5 days. FortiCloud SSO logins from new source IPs may indicate exploitation…
Description
This rule detects the first successful FortiCloud SSO login from a previously unseen source IP address to a FortiGate device within the last 5 days. FortiCloud SSO logins from new source IPs may indicate exploitation of SAML-based authentication bypass vulnerabilities such as CVE-2026-24858, where crafted SAML assertions allow unauthorized access to FortiGate devices registered to other accounts. Environments that regularly use FortiCloud SSO will only alert on new source IPs not seen in the lookback window.
Detection logic
Its licence does not clear it for publishing here
Sunturai publishes a detection's own text where the licence it arrived under has been reviewed and permits it, and Elastic License 2.0 has not. The query as its source wrote it, its canonical form and the hash that pins this revision are in the workspace record.
Detection requirements
- Platform
- ContainersESXiIaaSIdentity ProviderLinuxmacOSNetwork DevicesOffice SuiteSaaSWindows
The rule states no platform. This is derived from the 3 ATT&CK techniques it maps to.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
References
| Reference | Cited by |
|---|---|
| www.cisa.gov/news-events/alerts/2026/01/28/fortinet-releases-guidance-address-ongoing-exploitation-authentication-bypass-vulnerability-cve-2026 | 8 |
| www.elastic.co/docs/reference/integrations/fortinet_fortigate | 11 |
| www.fortiguard.com/psirt/FG-IR-26-060 | 6 |
| www.fortinet.com/blog/psirt-blogs/analysis-of-sso-abuse-on-fortios | 6 |
From the source
- At source
- Open at source
- Upstream identifier
- 618a219d-a363-4ab1-ba30-870d7c22facd
- Tagged by the source as
- Data Source: FortinetData Source: Fortinet FortiGateDomain: IdentityDomain: NetworkNoise: LowPerformance: NormalProfile: RecommendedResources: Investigation GuideRule Type: ES|QLTactic: Credential AccessTactic: Initial AccessThreat: Vulnerability ExploitUse Case: Threat DetectionVuln: CVE-2026-24858
Licence
- Published under
- Elastic License 2.0Read the licence
- Attribution
- Required
Authorship
- Written by
- Published
- Sep 29, 2026
- Version
- 4