Fortinet patches actively exploited FortiOS SSO auth bypass (CVE-2026-24858)

Security Affairs

January 28, 2026 at 3:53 PM

Actively Exploited

Overview

Fortinet has issued patches for a serious vulnerability in its FortiOS software, identified as CVE-2026-24858, which has been actively exploited by attackers. This flaw allows unauthorized users to bypass Single Sign-On (SSO) authentication, posing a significant risk to organizations using affected systems. The vulnerability has a high CVSS score of 9.4, indicating its severity. It impacts several products, including FortiOS, FortiManager, and FortiAnalyzer. Companies utilizing these systems should prioritize applying the available patches to protect against potential breaches.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: FortiOS, FortiManager, FortiAnalyzer
Action Required: Fortinet has started rolling out patches for CVE-2026-24858.
Timeline: Newly disclosed

Original Article Summary

Fortinet released fixes for a critical FortiOS SSO auth bypass (CVE-2026-24858) actively exploited, impacting FortiOS, FortiManager, and FortiAnalyzer. Fortinet started rolling out patches for a critical FortiOS flaw under active attack. The bug, CVE-2026-24858 (CVSS score of 9.4), lets attackers bypass authentication via SSO. It affects FortiOS, FortiManager, and FortiAnalyzer, while Fortinet checks if other […]

Impact

FortiOS, FortiManager, FortiAnalyzer

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Newly disclosed

Remediation

Fortinet has started rolling out patches for CVE-2026-24858. Users are advised to apply these patches immediately to mitigate the risk of exploitation.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Fortinet, Vulnerability, and 1 more.

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