Automated FortiGate Attacks Exploit FortiCloud SSO to Alter Firewall Configurations
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2025-59718 | Critical FortiCloud SSO Authentication Bypass in Fortinet FortiOS and FortiProxy CVE-2025-59718 is a critical (CVSS 9.8) improper verification of cryptographic signature flaw (CWE-347) in the FortiCloud SSO login flow of Fortinet FortiOS, FortiProxy, and FortiSwitchManager, with the Siemens RUGGEDCOM APE1808 appliance also listed in the CVE's affected CPE entries. An unauthenticated attacker who can reach a device's FortiCloud SSO login can submit a crafted SAML response message whose cryptographic signature is not properly verified, bypassing authentication entirely. The bypass grants unauthorized access to the affected device with high impact on confidentiality, integrity, and availability, typically administrative control of the management interface. Any organization running the affected FortiOS 7.0–7.6, FortiProxy 7.0–7.6, or FortiSwitchManager 7.0–7.2 versions that uses FortiCloud SSO for administrative login is exposed. Exploitation is confirmed in the wild: the flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2025-12-16, security reporting describes active attacks against FortiGate firewalls via this SAML SSO bypass, and EPSS assigns a 68.3% probability of exploitation within 30 days. Do: Upgrade all affected products out of the vulnerable ranges — FortiOS beyond 7.6.3/7.4.8/7.2.11/7.0.17, FortiProxy beyond 7.6.3/7.4.10/7.2.14/7.0.21, and FortiSwitchManager beyond 7.2.6/7.0.5 — using the fixed builds listed in Fortinet's security advisory, and patch Siemens RUGGEDCOM APE1808 firmware per Siemens guidance. As interim mitigation, disable or restrict FortiCloud SSO-based administrative login, limit management-interface exposure to trusted networks, and review admin/SSO logs for anomalous sign-ins or forged SAML responses. Given the KEV listing, US federal agencies must apply vendor mitigations or discontinue use of affected products per BOD 22-01. | 9.8 | 68% | KEV |
| masslikely on the order of 100,000+ internet-exposed FortiOS/FortiProxy systems (Fortinet's deployed base is in the millions); the directly exploitable set is the… | |
| CVE-2025-59719 | Unauthenticated SAML Signature Bypass in Fortinet FortiWeb (FortiCloud SSO) FortiWeb contains an improper verification of cryptographic signature (CWE-347) in its FortiCloud SSO login flow, allowing an unauthenticated attacker to bypass authentication by submitting a crafted SAML response whose signature is not properly validated. Because this requires no privileges or user interaction and is network-reachable, successful exploitation grants the attacker the access of a legitimate SSO-authenticated administrator to the appliance's management interface. The flaw affects FortiWeb 8.0.0, 7.6.0 through 7.6.4, and 7.4.0 through 7.4.9. Organizations running these versions are affected, particularly where the management interface is reachable and FortiCloud SSO login is enabled. As of this analysis the flaw is not in the CISA KEV catalog and no public proof-of-concept is known, but a closely related SAML SSO authentication bypass in FortiGate firewalls (CVE-2025-59718) is under active attack and Fortinet has issued urgent authentication patches, so elevated exploitation risk is plausible. Do: Upgrade FortiWeb to a patched release per Fortinet's PSIRT advisory covering CVE-2025-59719, prioritizing internet-facing appliances on 8.0.0, 7.6.x, or 7.4.x. As interim mitigation, restrict access to the management interface, disable or limit FortiCloud SSO login in favor of local or hardened admin authentication, and review SSO login logs for successful authentications from unexpected sources. Note that the sibling FortiGate SAML bypass (CVE-2025-59718) is being actively exploited, so treat this patch as urgent. | 9.8 | 29% |
| largetens of thousands of internet-exposed FortiWeb appliances (order of magnitude ~10k-100k), with the exploitable subset limited to deployments using FortiCloud… |
Full article326 words · extracted from thehackernews.com · click to collapse
Ravie LakshmananJan 22, 2026Network Security / Vulnerability
Cybersecurity company Arctic Wolf has warned of a "new cluster of automated malicious activity" that involves unauthorized firewall configuration changes on Fortinet FortiGate devices.
The activity, it said, commenced on January 15, 2026, adding it shares similarities with a December 2025 campaign in which malicious SSO logins on FortiGate appliances were recorded against the admin account from different hosting providers by exploiting CVE-2025-59718 and CVE-2025-59719.
Both vulnerabilities allow for unauthenticated bypass of SSO login authentication via crafted SAML messages when the FortiCloud single sign-on (SSO) feature is enabled on affected Devices. The shortcomings impact FortiOS, FortiWeb, FortiProxy, and FortiSwitchManager.
"This activity involved the creation of generic accounts intended for persistence, configuration changes granting VPN access to those accounts, as well as exfiltration of firewall configurations," Arctic Wolf said of the developing threat cluster.
Specifically, this entails carrying out malicious SSO logins against a malicious account "[email protected]" from four different IP addresses, following which the firewall configuration files are exported to the same IP addresses via the GUI interface. The list of source IP addresses is below -
- 104.28.244[.]115
- 104.28.212[.]114
- 217.119.139[.]50
- 37.1.209[.]19
In addition, the threat actors have been observed creating secondary accounts, such as "secadmin," "itadmin," "support," "backup," "remoteadmin," and "audit," for persistence.
"All of the above events took place within seconds of each other, indicating the possibility of automated activity," Arctic Wolf added.
The disclosure coincides with a post on Reddit in which multiple users reported seeing malicious SSO logins on fully-patched FortiOS devices, with one user stating the "Fortinet developer team has confirmed the vulnerability persists or is not fixed in version 7.4.10."
The Hacker News has reached out to Fortinet for comment, and we will update the story if we hear back. In the interim, it's advised to disable the "admin-forticloud-sso-login" setting.
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Text extracted automatically; images, tables and formatting may be missing. Original: https://thehackernews.com/2026/01/automated-fortigate-attacks-exploit.html