OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject malicious scripts by submitting crafted input to the mailserver parameter. Attackers can send POST requests to the monit interface with JavaScript payloads in the mailserver parameter to execute arbitrary code in users' browsers.
Advisories

No advisories yet.

Fixes

Solution

OPNsense 19.1.1 released


Workaround

No workaround given by the vendor.

History

Wed, 18 Feb 2026 19:15:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:opnsense:opnsense:19.1:*:*:*:*:*:*:*

Tue, 17 Feb 2026 17:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 17 Feb 2026 16:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Sun, 15 Feb 2026 14:15:00 +0000

Type Values Removed Values Added
Description OPNsense 19.1 contains a reflected cross-site scripting vulnerability that allows unauthenticated attackers to inject malicious scripts by submitting crafted input to the mailserver parameter. Attackers can send POST requests to the monit interface with JavaScript payloads in the mailserver parameter to execute arbitrary code in users' browsers.
Title OPNsense 19.1 Reflected XSS via monit interface
First Time appeared Opnsense
Opnsense opnsense
Weaknesses CWE-79
CPEs cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*
Vendors & Products Opnsense
Opnsense opnsense
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'}

cvssV4_0

{'score': 5.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-02-17T16:52:30.726Z

Reserved: 2026-02-15T13:21:00.205Z

Link: CVE-2019-25375

cve-icon Vulnrichment

Updated: 2026-02-17T14:49:47.797Z

cve-icon NVD

Status : Analyzed

Published: 2026-02-15T14:16:07.417

Modified: 2026-02-18T19:11:03.210

Link: CVE-2019-25375

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-02-16T09:42:53Z

Weaknesses