Fortinet Fortigate ZTNA Server Improper Certificate Validation (FG-IR-24-457)

high Nessus Plugin ID 270570

Synopsis

Fortinet Firewall is missing one or more security-related updates.

Description

The version of Fortigate installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the FG-IR-24-457 advisory.

- An Improper Validation of Certificate with Host Mismatch vulnerability [CWE-297] in FortiProxy version 7.6.1 and below, version 7.4.8 and below, 7.2 all versions, 7.0 all versions and FortiOS version 7.6.2 and below, version 7.4.8 and below, 7.2 all versions, 7.0 all versions ZTNA proxy may allow an unauthenticated attacker in a man-in-the middle position to intercept and tamper with connections to the ZTNA proxy (CVE-2025-25253)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

For 7.0.x / 7.2.x, see vendor advisory. For 7.4.x, upgrade to Fortigate version 7.4.9 or later. For 7.6.x, upgrade to Fortigate version 7.6.3 or later.

See Also

https://www.fortiguard.com/psirt/FG-IR-24-457

Plugin Details

Severity: High

ID: 270570

File Name: fortigate_FG-IR-24-457.nasl

Version: 1.1

Type: local

Family: Firewalls

Published: 10/15/2025

Updated: 10/15/2025

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Temporal Score: 5

Vector: CVSS2#AV:A/AC:H/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2025-25253

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:fortinet:fortios

Required KB Items: Host/Fortigate/model, Host/Fortigate/version

Exploit Ease: No known exploits are available

Patch Publication Date: 10/14/2025

Vulnerability Publication Date: 10/14/2025

Reference Information

CVE: CVE-2025-25253