What is CVE-2026-3343?

CVE-2026-3343 is a medium-severity vulnerability in Watchguard Fireboxcloud, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-03-03.

How severe is CVE-2026-3343?

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

XSS in Watchguard Fireboxcloud

CVE-2026-3343

A reflected cross-site scripting (XSS) vulnerability in the Fireware OS Web UI enabled execution of malicious JavaScript in the context of an authenticated management user's browser when they click on a specially crafted link.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (9.6th percentile) — read the EPSS interpretation.

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.

Affected products

Watchguard Fireboxcloud
Watchguard Firebox_m270
Watchguard Firebox_m290
Watchguard Firebox_m295
Watchguard Firebox_m370
Watchguard Firebox_m390
Watchguard Firebox_m395
Watchguard Firebox_m440
Watchguard Firebox_m4600
Watchguard Firebox_m470

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

5d1c2695-1a31-4499-88ae-e847036fd7e3 (Vendor Advisory)
5d1c2695-1a31-4499-88ae-e847036fd7e3 (vendor-advisory)

Frequently asked questions

What is CVE-2026-3343?: CVE-2026-3343 is a medium-severity vulnerability in Watchguard Fireboxcloud, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-03-03.
How severe is CVE-2026-3343?: Medium severity. CVSS v3 base score is 6.1 out of 10.