CVE-2026-49131 — MEDIUM (5.4)

Vulnerability Description

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 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality

LOW

Integrity

LOW

Availability

NONE

Related Weaknesses (CWE)

CWE-79

References

FAQ

What is CVE-2026-49131?

CVE-2026-49131 is a vulnerability with a CVSS score of 5.4 (MEDIUM). 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 embed...

How severe is CVE-2026-49131?

CVE-2026-49131 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-49131?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.