FortiOS
CVE-2025-31366: Improper Neutralization of Input During Web Page Generation in FortiSASE, FortiOS and others
An Improper Neutralization of Input During Web Page Generation vulnerability [CWE-79] vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2 all versions, FortiOS 7.0 all versions, FortiOS 6.4 all versions, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4 all versions, FortiProxy 7.2 all versions, FortiProxy 7.0 all versions, FortiSASE 25.2.a may allow an unauthenticated attacker to perform a reflected cross site scripting (XSS) via crafted HTTP requests.
Published
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| FortiSASE 25.2 | See the advisory |
| FortiOS 7.6.0 to 7.6.2 | 7.6.4 or later |
| FortiOS 7.4.0 to 7.4.7 | 7.4.9 or later |
| FortiOS 7.2.0 to 7.2.13 | Upgrade past 7.2.13; see the advisory |
| FortiOS 7.0.0 to 7.0.19 | Upgrade past 7.0.19; see the advisory |
| FortiOS 6.4.0 to 6.4.16 | Upgrade past 6.4.16; see the advisory |
| FortiProxy 7.6.0 to 7.6.3 | 7.6.4 or later |
| FortiProxy 7.4.0 to 7.4.8 | Upgrade past 7.4.8; see the advisory |
| FortiProxy 7.2.0 to 7.2.16 | Upgrade past 7.2.16; see the advisory |
| FortiProxy 7.0.0 to 7.0.23 | Upgrade past 7.0.23; see the advisory |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
An Improper Neutralization of Input During Web Page Generation vulnerability [CWE-79] vulnerability in Fortinet FortiOS 7.6.0 through 7.6.3, FortiOS 7.4.0 through 7.4.8, FortiOS 7.2 all versions, FortiOS 7.0 all versions, FortiOS 6.4 all versions, FortiProxy 7.6.0 through 7.6.3, FortiProxy 7.4 all versions, FortiProxy 7.2 all versions, FortiProxy 7.0 all versions, FortiSASE 25.2.a may allow an unauthenticated attacker to perform a reflected cross site scripting (XSS) via crafted HTTP requests.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 10 Oct 2026.