CVE-2026-13374 PUBLISHED

WatchGuard Firebox Stored Cross-Site-Scripting (XSS) Vulnerability in ConnectWise Technology Integration Configuration

Assigner: WatchGuard
Reserved: 25.06.2026 Published: 02.07.2026 Updated: 03.07.2026

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS (ConnectWise Technology Integration module) allows Stored XSS. This vulnerability is an additional unmitigated attack path for CVE-2025-13937.

This issue affects Fireware OS 12.4 up to and including 12.12, 12.5 up to and including 12.5.18, and 2025.1 up to and including 2026.2.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
CVSS Score: 4.8

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	Low
Attack Complexity	Low	Integrity	None	Integrity	Low
Attack Requirements	None	Availability	None	Availability	None
Privileges Required	High
User Interaction	Passive

CVSS 4.0

Product Status

Vendor	WatchGuard
Product	Fireware OS
Versions	Default: unaffected affected from 12.4 to 12.12 (incl.) affected from 12.5 to 12.5.18 (incl.) affected from 2025.1 to 2026.2 (incl.)

Credits

Simone Paganessi (https://www.linkedin.com/in/simonepaganessi) finder

References

https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2026-00016

Problem Types

CWE-79 Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') CWE

Impacts

CAPEC-592 Stored XSS