What is CVE-2026-3987?

CVE-2026-3987 is a high-severity vulnerability in Watchguard Firebox Cloud, classified under Path Traversal. CVSS score: 7.2/10. Published 2026-04-01.

How severe is CVE-2026-3987?

High severity. CVSS v3 base score is 7.2 out of 10.

Path Traversal in Watchguard Firebox Cloud

CVE-2026-3987

A path traversal vulnerability in the Fireware OS Web UI on WatchGuard Firebox systems may allow a privileged authenticated remote attacker to execute arbitrary code in the context of an elevated system process.

Vulnerability class: Path Traversal (Directory Traversal)

EPSS: 0.006 (44.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CWE-22 — Path Traversal

References

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

Frequently asked questions

What is CVE-2026-3987?: CVE-2026-3987 is a high-severity vulnerability in Watchguard Firebox Cloud, classified under Path Traversal. CVSS score: 7.2/10. Published 2026-04-01.
How severe is CVE-2026-3987?: High severity. CVSS v3 base score is 7.2 out of 10.