Is CVE-2025-62826 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2025-62826 being exploited in the wild.

How severe is CVE-2025-62826?

Low severity, with a CVSS score of 3.1, published 14 July 2026.

Which products and versions are affected?

Fortinet FortiOS 7.6.0 through 7.6.4, 7.4 all versions, 7.2 all versions; Fortinet FortiProxy 7.6.0 through 7.6.4, 7.4 all versions, 7.2 all versions.

Is there a fix for CVE-2025-62826?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2025-62826 attacked?

It is attacked over the network, in an operating system.

Am I affected by CVE-2025-62826?

Check whether you run Fortinet FortiOS or Fortinet FortiProxy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2025-62826: Fortinet FortiOS and FortiProxy HTTP Response Splitting in captive portal

CVE-2025-62826 · Severity: low · CVSS 3.1 · Published 2026-07-14

A security vulnerability exists in the captive portal authentication system of Fortinet firewalls and web proxies. An attacker who can intercept a user's login request could inject malicious data into the web response, potentially leading to session manipulation or further web-based attacks. This issue primarily affects organizations using captive portals for guest or user network access.

Technologies: Fortinet FortiOS, Fortinet FortiProxy. Vendors: Fortinet.

Quick answers

Is CVE-2025-62826 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2025-62826 being exploited in the wild.
How severe is CVE-2025-62826?: Low severity, with a CVSS score of 3.1, published 14 July 2026.
Which products and versions are affected?: Fortinet FortiOS 7.6.0 through 7.6.4, 7.4 all versions, 7.2 all versions; Fortinet FortiProxy 7.6.0 through 7.6.4, 7.4 all versions, 7.2 all versions.
Is there a fix for CVE-2025-62826?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2025-62826 attacked?: It is attacked over the network, in an operating system.
Am I affected by CVE-2025-62826?: Check whether you run Fortinet FortiOS or Fortinet FortiProxy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An HTTP Response Splitting vulnerability (CWE-113) exists in the captive portal authentication component of FortiOS and FortiProxy. The flaw is caused by improper neutralization of CRLF sequences in HTTP headers. An attacker who can perform a Man-in-the-Middle (MitM) interception of a user's authentication request can modify the request to inject arbitrary headers into the resulting HTTP response. This requires the attacker to be in a position to intercept and modify traffic (AC:H) and involves user interaction (UI:R). Fortinet recommends upgrading to FortiOS/FortiProxy version 7.6.5 or migrating from the affected 7.2 and 7.4 branches.

Affected products

Fortinet FortiOS 7.6.0 through 7.6.4, 7.4 all versions, 7.2 all versions
Fortinet FortiProxy 7.6.0 through 7.6.4, 7.4 all versions, 7.2 all versions

Timeline

2026-07-14: disclosed
2026-07-14: advisory: FG-IR-26-153 published

References

https://fortiguard.fortinet.com/psirt/FG-IR-26-153

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