What is the CVSS score of CVE-2019-25375?

CVE-2019-25375 has a CVSS 3.1 base score of 6.1 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.0%.

Which versions of Opnsense are affected by CVE-2019-25375?

Organizations using OPNsense 19.1 should be aware of moderate risk from CVE-2019-25375, a cross-site scripting vulnerability rated CVSS 6.1.

Is there a public PoC exploit available for CVE-2019-25375?

Yes, a public proof-of-concept exploit is available for CVE-2019-25375. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2019-25375?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Verify Content-Security-Policy and output encoding.

Opnsense CVE-2019-25375

MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2026-02-15 disclosure@vulncheck.com

XSS Opnsense

6.1

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.1 MEDIUM

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:54 vuln.today

PoC Detected

Feb 18, 2026 - 19:11 vuln.today

Public exploit code

CVE Published

Feb 15, 2026 - 14:16 nvd

MEDIUM 6.1

DescriptionCVE.org

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.

AnalysisAI

Technical ContextAI

Classified as CWE-79 (Cross-site Scripting (XSS)). Affects the mailserver component of Opnsense. 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.

RemediationAI

Monitor vendor advisories for a patch. Implement output encoding and Content Security Policy headers. Restrict network access to the affected service where possible.