What is CVE-2021-36176?

CVE-2021-36176 is a medium-severity vulnerability in Fortinet Fortiportal, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-11-02.

How severe is CVE-2021-36176?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Fortinet Fortiportal

CVE-2021-36176

Multiple uncontrolled resource consumption vulnerabilities in the web interface of FortiPortal before 6.0.6 may allow a single low-privileged user to induce a denial of service via multiple HTTP requests.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2021-11-02 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.006 (45.6th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Fortinet Fortiportal — versions FortiPortal before 6.0.6
Fortinet Fortiportal

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

fortiguard.com/advisory/FG-IR-21-100 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-36176?: CVE-2021-36176 is a medium-severity vulnerability in Fortinet Fortiportal, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-11-02.
How severe is CVE-2021-36176?: Medium severity. CVSS v3 base score is 6.1 out of 10.