CVE-2019-25377

Medium
|4.8
No Exploit

Plain English Summary

AI-powered analysis for quick understanding

This vulnerability allows attackers to run malicious JavaScript in the web browser of users who are logged into the OPNsense system, potentially stealing their session cookies or other sensitive information. It requires the attacker to send specially crafted requests to a specific part of the system while the user is authenticated.

Technical Description

OPNsense 19.1 contains a reflected cross-site scripting vulnerability in the system_advanced_sysctl.php endpoint that allows attackers to inject malicious scripts via the value parameter. Attackers can craft POST requests with script payloads in the value parameter to execute JavaScript in the context of authenticated user sessions.

CVSS Vector Analysis

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionRequired
Confidentiality ImpactHigh
Integrity ImpactHigh
Availability ImpactHigh
ScopeChanged

Vector String

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Exploit Resources

Search for proof-of-concept code and exploit modules

Official References

Est. Bounty
$638($500-$1K)
Vendor Response
Grade APatched in 3 days

Quick Information

Published

Feb 15, 2026

about 2 months ago

Last Modified

Feb 18, 2026

about 2 months ago

Vendor

opnsense

Product

opnsense

Related Vulnerabilities

CVE-2019-25376Medium

This vulnerability allows attackers to run malicious scripts in the browsers of users visiting the OPNsense web interface, potentially stealing sensitive information or performing actions on behalf of the user. To exploit this, attackers need to send specially crafted requests to the system without needing to log in.

CVE-2019-25375Medium

This vulnerability allows attackers to inject harmful scripts into users' browsers by sending specially crafted requests to the mailserver parameter on the OPNsense interface. It requires no authentication, meaning anyone can exploit it if they know how to send the right type of request.

CVE-2019-25374Medium

This vulnerability allows attackers to inject harmful scripts into users' browsers by exploiting a specific parameter in OPNsense's VPN settings. To succeed, the attacker needs to send specially crafted requests that include malicious JavaScript, which can then execute unwanted actions on the user's device when they access the affected page.

CVE-2019-25373Medium

This vulnerability allows an attacker to inject harmful scripts that can run in the web browsers of other users who view certain firewall rule pages. To exploit this, the attacker must be authenticated and can send specially crafted data through a specific form field.

CVE-2019-25372Medium

An attacker can inject harmful scripts into a user's browser session, allowing them to execute arbitrary JavaScript when the user visits a specific page on the OPNsense system. This vulnerability can be exploited by sending specially crafted requests without needing to log in, making it easier for attackers to target unsuspecting users.