CVE-2026-49131
MEDIUMOPNsense < 26.1.9 Stored XSS via Firewall Rule Description Field
Title source: cnaDescription
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.
References (3)
Core 3
Core References
Release Notes release-notes
Release Notes
https://docs.opnsense.org/releases/CE_26.1.html#june-02-2026
Patch patch
Patch Commit
https://github.com/opnsense/core/commit/b11d6b340716e240868ab19a369e058a46f0876f
Third Party Advisory third-party-advisory
https://www.vulncheck.com/advisories/opnsense-stored-xss-via-firewall-rule-description-field
Scores
CVSS v3
5.4
EPSS
0.0016
EPSS Percentile
6.2%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-79
Status
published
Products (1)
Deciso B.V./OPNsense
< 26.1.9
Published
Aug 03, 2026
Tracked Since
Aug 04, 2026