# CVE-2025-53379: Fortinet FortiAuthenticator out-of-bounds read in GUI

Source: https://junglewise.ai/threats/cve-2025-53379-fortinet-fortiauthenticator-out-of-bounds-read-in-gui  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-07-14  
License: CC BY 4.0 with a link back

CVE-2025-53379 · Severity: high · CVSS 7.5 · Published 2026-07-14

FortiAuthenticator is a centralized identity management appliance used to manage user authentication and single sign-on across a network. A security flaw in its web management interface could allow an unauthorized person to access sensitive system information by sending a specially crafted network request. This could lead to the exposure of data that might be used to further compromise the organization's security infrastructure.

Technologies: [Fortinet FortiAuthenticator](https://junglewise.ai/threats/technologies/fortiauthenticator). Vendors: [Fortinet](https://junglewise.ai/threats/vendors/fortinet).

## Quick answers

**Is CVE-2025-53379 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-53379 being exploited in the wild.

**How severe is CVE-2025-53379?** High severity, with a CVSS score of 7.5, published 14 July 2026.

**Which products and versions are affected?** Fortinet FortiAuthenticator 6.6.0 through 6.6.2, 6.5.0 through 6.5.7.

**Is there a fix for CVE-2025-53379?** 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-2025-53379 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2025-53379?** Check whether you run Fortinet FortiAuthenticator 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 out-of-bounds read vulnerability (CWE-125) exists in the GUI component of Fortinet FortiAuthenticator. The flaw is triggered when the application fails to properly validate the boundaries of a buffer while processing a specially crafted HTTP request. A remote, unauthenticated attacker can exploit this to read memory contents that should be inaccessible, potentially leading to the disclosure of sensitive information. The vulnerability affects versions 6.6.0 through 6.6.2 and all versions in the 6.5 branch. Users are advised to upgrade to version 6.6.3 or the upcoming 6.5.8 release.

## Affected products

- Fortinet FortiAuthenticator 6.6.0 through 6.6.2, 6.5.0 through 6.5.7

## Timeline

- 2026-07-14: disclosed: Initial publication of the advisory by Fortinet
- 2026-07-14: advisory: NVD record published

## References

- [https://fortiguard.fortinet.com/psirt/FG-IR-26-146](https://fortiguard.fortinet.com/psirt/FG-IR-26-146)

## Related threats

- [Fortinet FortiAuthenticator hard-coded password authentication bypass](https://junglewise.ai/threats/cve-2026-126257-a-use-of-hard-coded-password-vulnerability-in-fortinet)
- [Fortinet FortiAuthenticator SQL injection](https://junglewise.ai/threats/cve-2026-126252-a-improper-neutralization-of-special-elements-used-in-an-sql)
- [Fortinet FortiAuthenticator incorrect authorization](https://junglewise.ai/threats/cve-2026-126251-a-incorrect-authorization-vulnerability-in-fortinet)
- [Fortinet FortiAuthenticator authorization bypass DoS](https://junglewise.ai/threats/cve-2026-126250-a-incorrect-authorization-vulnerability-in-fortinet)
- [Fortinet FortiAuthenticator privilege escalation in GUI](https://junglewise.ai/threats/cve-2026-126249-a-improper-privilege-management-vulnerability-in-fortinet)