What is CVE-2021-22128?

CVE-2021-22128 is a high-severity vulnerability in Fortinet Fortiproxy. CVSS score: 7.1/10. Published 2021-03-04.

How severe is CVE-2021-22128?

High severity. CVSS v3 base score is 7.1 out of 10.

Vulnerability in Fortinet Fortiproxy

CVE-2021-22128

An improper access control vulnerability in FortiProxy SSL VPN portal 2.0.0, 1.2.9 and below versions may allow an authenticated, remote attacker to access internal service such as the ZebOS Shell on the FortiProxy appliance through the Quick Connection functionality.

Published 2021-03-04 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H.

EPSS exploit prediction

EPSS: 0.010 (62.5th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 62nd percentile — 62.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: +0.000

Affected products

Fortinet Fortiproxy — versions FortiProxy 2.0.0, 1.2.9 and below
Fortinet Fortiproxy — versions 2.0.0

References

fortiguard.com/advisory/FG-IR-20-235 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-22128?: CVE-2021-22128 is a high-severity vulnerability in Fortinet Fortiproxy. CVSS score: 7.1/10. Published 2021-03-04.
How severe is CVE-2021-22128?: High severity. CVSS v3 base score is 7.1 out of 10.