CVE-2026-49131

OPNsense before 26.1.9 contains a stored cross-site scripting vulnerability that allows authenticated attackers with firewall rule management privileges to inject arbitrary HTML or JavaScript by embedding payloads in the firewall rule description field via the filter API endpoint. The unsanitized description value is persisted and later rendered through the default cell formatter in opnsense_bootgrid.js, which assigns raw cell content to innerHTML, causing injected scripts to execute in the browser of any authenticated user who views the Firewall Rules page, enabling session hijacking or credential theft.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://docs.opnsense.org/releases/CE_26.1.html#june-02-2026
https://github.com/opnsense/core/commit/b11d6b340716e240868ab19a369e058a46f0876f
https://www.vulncheck.com/advisories/opnsense-stored-xss-via-firewall-rule-description-field

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-03 21:16

Updated : 2026-09-16 20:32

NVD link : CVE-2026-49131

Mitre link : CVE-2026-49131

CVE.ORG link : CVE-2026-49131

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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