# CVE-2026-3987: A path traversal vulnerability in the Fireware OS Web UI on WatchGuard Firebox systems may allow a privileged…

Source: https://junglewise.ai/threats/cve-2026-3987-a-path-traversal-vulnerability-in-the-fireware-os-web-ui-on  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-01  
License: CC BY 4.0 with a link back

CVE-2026-3987 · Severity: high · CVSS 7.2 · Published 2026-04-01

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.

Technologies: [Watchguard Fireware](https://junglewise.ai/threats/technologies/fireware). Vendors: [Watchguard](https://junglewise.ai/threats/vendors/watchguard).

## Quick answers

**Is CVE-2026-3987 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-3987 being exploited in the wild.

**How severe is CVE-2026-3987?** High severity, with a CVSS score of 7.2, published 1 April 2026.

**Which products and versions are affected?** Watchguard Firebox Cloud, Watchguard Firebox M270, Watchguard Firebox M290, Watchguard Firebox M295 and 33 more. The advisory does not name versions.

**Is there a fix for CVE-2026-3987?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**Am I affected by CVE-2026-3987?** Check whether you run Watchguard Firebox Cloud, Watchguard Firebox M270, Watchguard Firebox M290 or one of the others listed. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Affected products

- Watchguard Firebox Cloud
- 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
- Watchguard Firebox M4800
- Watchguard Firebox M495
- Watchguard Firebox M5600
- Watchguard Firebox M570
- Watchguard Firebox M5800
- Watchguard Firebox M590
- Watchguard Firebox M595
- Watchguard Firebox M670
- Watchguard Firebox M690
- Watchguard Firebox M695
- Watchguard Firebox Nv5
- Watchguard Firebox T115-W
- Watchguard Firebox T125
- Watchguard Firebox T125-W
- Watchguard Firebox T145
- Watchguard Firebox T145-W
- Watchguard Firebox T185
- Watchguard Firebox T20
- Watchguard Firebox T25
- Watchguard Firebox T40
- Watchguard Firebox T45
- Watchguard Firebox T55
- Watchguard Firebox T70
- Watchguard Firebox T80
- Watchguard Firebox T85
- Watchguard Fireboxv
- Watchguard Fireware

## Related threats

- [WatchGuard Fireware OS out-of-bounds write in wgagent](https://junglewise.ai/threats/cve-2026-13384-watchguard-fireware-os-out-of-bounds-write-in-wgagent)
- [WatchGuard Fireware OS DoS via NULL pointer dereference in iked](https://junglewise.ai/threats/cve-2026-13084-watchguard-fireware-os-dos-via-null-pointer-dereference-in-iked)
- [WatchGuard Fireware OS path traversal in Management Web UI](https://junglewise.ai/threats/cve-2026-13054-watchguard-fireware-os-path-traversal-in-management-web-ui)
- [WatchGuard Fireware OS out-of-bounds write in networkd](https://junglewise.ai/threats/cve-2026-13050-watchguard-fireware-os-out-of-bounds-write-in-networkd)
- [WatchGuard Fireware OS out-of-bounds write in iked process](https://junglewise.ai/threats/cve-2025-14733-watchguard-fireware-os-out-of-bounds-write-in-iked-process)