CVE-2026-121528
Last modified
CVE-2026-121528 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. A improper certificate validation vulnerability in Fortinet FortiOS 7.6.0 through 7.6.4, FortiOS 7.4.0 through 7.4.9, FortiOS 7.2.0 through 7.2.13, FortiOS 7.0 all versions, FortiOS 6.4 all versions may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the SSLVPN web portal and the backend destination website.. EPSS estimates a 0.24% chance of exploitation in the next 30 days.
Description
A improper certificate validation vulnerability in Fortinet FortiOS 7.6.0 through 7.6.4, FortiOS 7.4.0 through 7.4.9, FortiOS 7.2.0 through 7.2.13, FortiOS 7.0 all versions, FortiOS 6.4 all versions may allow a remote and unauthenticated attacker to perform a Man-in-the-Middle attack on the communication channel between the SSLVPN web portal and the backend destination website.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Fortinet | FortiOS | >= 7.6.0, <= 7.6.4; >= 7.4.0, <= 7.4.9; >= 7.2.0, <= 7.2.13; >= 7.0.0, <= 7.0.19; >= 6.4.0, <= 6.4.16 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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