TI-2021-08044 Aliases CVE-2021-26092 GHSA-mpgj-7qvh-h4r8

Cross-site scripting in Fortinet FortiOS, FortiProxy

LOW 29CWE-79Published 2022-02-24 · Updated 2024-10-22

Key facts

Attack vector: Network
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: Cross-site scripting
Confidentiality · integrity · availability: Low · Low · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-79.

Summary

Failure to sanitize input in the SSL VPN web portal of FortiOS 5.2.10 through 5.2.15, 5.4.0 through 5.4.13, 5.6.0 through 5.6.14, 6.0.0 through 6.0.12, 6.2.0 through 6.2.7, 6.4.0 through 6.4.4; and FortiProxy 1.2.0 through 1.2.9, 2.0.0 through 2.0.1 may allow a remote unauthenticated attacker to perform a reflected Cross-site Scripting (XSS) attack by sending a request to the error page with malicious GET parameters.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.01077 65th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Fortinet	Fortinet FortiOS, FortiProxy	FortiOS 5.2.10 through 5.2.15, 5.4.0 through 5.4.13, 5.6.0 through 5.6.14, 6.0.0 through 6.0.12, 6.2.0 through 6.2.7, 6.4.0 through 6.4.4; FortiProxy 1.2.0 through 1.2.9, 2.0.0 through 2.0.1	—	No fix listed	CNA

Fortinet FortiOS, FortiProxy VendorFortinet Affected FortiOS 5.2.10 through 5.2.15, 5.4.0 through 5.4.13, 5.6.0 through 5.6.14, 6.0.0 through 6.0.12, 6.2.0 through 6.2.7, 6.4.0 through 6.4.4; FortiProxy 1.2.0 through 1.2.9, 2.0.0 through 2.0.1 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPE	Versions	Role	Vendor
cpe:2.3:a:fortinet:fortiproxy::::::::	1.2.0 – 1.2.9	Vulnerable	Fortinet
cpe:2.3:a:fortinet:fortiproxy:2.0.0:::::::*	2.0.0	Vulnerable	Fortinet
cpe:2.3:a:fortinet:fortiproxy:2.0.1:::::::*	2.0.1	Vulnerable	Fortinet
cpe:2.3:o:fortinet:fortios::::::::	5.2.10 – 5.2.15; 5.4.0 – 5.4.13; 5.6.0 – 5.6.14; 6.0.0 – 6.0.12; 6.2.0 – 6.2.7; 6.4.0 – 6.4.4	Vulnerable	Fortinet

cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:* Versions 1.2.0 – 1.2.9 Vulnerable ·Fortinet
cpe:2.3:a:fortinet:fortiproxy:2.0.0:*:*:*:*:*:*:* Versions 2.0.0 Vulnerable ·Fortinet
cpe:2.3:a:fortinet:fortiproxy:2.0.1:*:*:*:*:*:*:* Versions 2.0.1 Vulnerable ·Fortinet
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:* Versions 5.2.10 – 5.2.15; 5.4.0 – 5.4.13; 5.6.0 – 5.6.14; 6.0.0 – 6.0.12; 6.2.0 – 6.2.7; 6.4.0 – 6.4.4 Vulnerable ·Fortinet

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-26092
2026-10-03 Alias added: GHSA-mpgj-7qvh-h4r8

References

Advisory 1

https://fortiguard.com/psirt/FG-IR-20-199

TI-2026-20057 Authentication bypass in Fortinet FortiWeb KEVCVSS 3.1CRITICAL 9.4
TI-2025-18911 Heap-based buffer overflow in Fortinet FortiSwitchManager KEVCVSS 3.1CRITICAL 9.8
TI-2024-36904 Authentication bypass in Fortinet FortiOS KEVCVSS 3.1CRITICAL 9.8
TI-2024-15234 A use of externally-controlled format string in Fortinet FortiOS versions 7.4.0 through… KEVCVSS 3.1CRITICAL 9.8
TI-2024-14448 Out-of-bounds write in Fortinet FortiOS KEVCVSS 3.1CRITICAL 9.8
TI-2023-12585 Heap-based buffer overflow in Fortinet FortiOS-6K7K KEVCVSS 3.1CRITICAL 9.8

See all 276 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences