Phone : +91 95 8290 7788 | Email : sales@itmonteur.net

Register & Request Quote | Submit Support Ticket

Home » Cyber Security News » Vulnerabilities & Exploits » Fortinet Patches CVE-2026-24858 After Active FortiOS SSO Exploitation Detected

Fortinet Patches CVE-2026-24858 After Active FortiOS SSO Exploitation Detected

Fortinet Patches CVE-2026-24858 After Active FortiOS SSO Exploitation Detected

https://firewalls.firm.in/wp-content/uploads/2026/01/1769595147_26_fortinet.jpg

Ravie LakshmananJan 28, 2026Network Security / Zero-Day

Fortinet has begun releasing security updates to address a critical flaw impacting FortiOS that has come under active exploitation in the wild.

The vulnerability, assigned the CVE identifier CVE-2026-24858 (CVSS score: 9.4), has been described as an authentication bypass related to FortiOS single sign-on (SSO). The flaw also affects FortiManager and FortiAnalyzer. The company said it’s continuing to investigate if other products, including FortiWeb and FortiSwitch Manager, are impacted by the flaw.

“An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] in FortiOS, FortiManager, FortiAnalyzer may 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,” Fortinet said in an advisory released Tuesday.

It’s worth noting that the FortiCloud SSO login feature is not enabled in the default factory settings. It’s only turned on in scenarios where an administrator registers the device to FortiCare from the device’s GUI, unless they have taken steps to explicitly toggle the “Allow administrative login using FortiCloud SSO” switch.

The development comes days after Fortinet confirmed that unidentified threat actors were abusing a “new attack path” to achieve SSO logins without requiring any authentication. The access was abused to create local admin accounts for persistence, make configuration changes granting VPN access to those accounts, and exfiltrate those firewall configurations.

Cybersecurity

Over the past week, the network security vendor said it has taken the following steps –

  • Locked out two malicious FortiCloud accounts (cloud-noc@mail.io and cloud-init@mail.io) on January 22, 2026
  • Disabled FortiCloud SSO on the FortiCloud side on January 26, 2026
  • Re-enabled FortiCloud SSO on January 27, 2026, while disabling the option to login from devices running vulnerable versions

In other words, customers are required to upgrade to the latest versions of the software for the FortiCloud SSO authentication to function. Fortinet is also urging users who detect signs of compromise to treat their devices as breached and recommends the following actions –

  • Ensure the device is running the latest firmware version
  • Restore configuration with a known clean version or audit for any unauthorized changes
  • Rotate credentials, including any LDAP/AD accounts that may be connected to the FortiGate devices

The development has led the U.S. Cybersecurity and Infrastructure Security Agency (CISA) to add CVE-2026-24858 to its Known Exploited Vulnerabilities (KEV) catalog, mandating Federal Civilian Executive Branch (FCEB) agencies to remediate the issues by January 30, 2026.

Information Security - InfoSec - Cyber Security - Firewall Providers Company in India

Juniper Firewall
Cisco Firewall
Checkpoint Firewall
paloalto Firewall
Fortinet Firewall
Forcepoint Firewall

 

Sophos Firewall
WatchGuard Firewall
Barracuda Firewall
Sonicwall Firewall
GajShield Firewall
Seqrite Firewall

 

 

 

 

 

 

 

 

 

 

 

What is Firewall? A Firewall is a network security device that monitors and filters incoming and outgoing network traffic based on an organization's previously established security policies. At its most basic, a firewall is essentially the barrier that sits between a private internal network and the public Internet.

 

Secure your network at the gateway against threats such as intrusions, Viruses, Spyware, Worms, Trojans, Adware, Keyloggers, Malicious Mobile Code (MMC), and other dangerous applications for total protection in a convenient, affordable subscription-based service. Modern threats like web-based malware attacks, targeted attacks, application-layer attacks, and more have had a significantly negative effect on the threat landscape. In fact, more than 80% of all new malware and intrusion attempts are exploiting weaknesses in applications, as opposed to weaknesses in networking components and services. Stateful firewalls with simple packet filtering capabilities were efficient blocking unwanted applications as most applications met the port-protocol expectations. Administrators could promptly prevent an unsafe application from being accessed by users by blocking the associated ports and protocols.

 

Firewall Firm is an IT Monteur Firewall Company provides Managed Firewall Support, Firewall providers , Firewall Security Service Provider, Network Security Services, Firewall Solutions India , New Delhi - India's capital territory , Mumbai - Bombay , Kolkata - Calcutta , Chennai - Madras , Bangaluru - Bangalore , Bhubaneswar, Ahmedabad, Hyderabad, Pune, Surat, Jaipur, Firewall Service Providers in India

Sales Number : +91 95 8290 7788 | Support Number : +91 94 8585 7788
Sales Email : sales@itmonteur.net | Support Email : support@itmonteur.net

Register & Request Quote | Submit Support Ticket

Firewall Firm is a Managed Firewall Security Solution Provider Company in India | Digital Marketing by SEO Company India | Powered by IT Monteur