CVE-2026-58394

EUVD-2026-102135

15.10.2026, 16:18

OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, src/www/system_advanced_admin.php reads certificate records into $a_cert but omits that array from legacy_html_escape_form_data() before rendering each certificate descr value in the SSL Certificate selector. The certificate description accepts HTML metacharacters, allowing a user with the page-system-certmanager privilege to store markup that executes when another user opens System Settings Administration. This issue is fixed in version 26.1.11.

Cross-site Scripting

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
GitHub_M	CNA	5.2 MEDIUM	NETWORK	LOW	HIGH	CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:L/A:N

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Early Detection

Affected products identified ahead of NVD analysis through intelligence sources.

Vendor	Product	Version	Source
opnsense	opnsense	𝑥 < 26.1.11	CNA

Common Weakness Enumeration

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

References

https://github.com/opnsense/core/commit/9d0a590e9c49f4374a5539929b366123f63bc9eb

https://github.com/opnsense/core/commit/adcb02f8f68071e636bf9660b2cb8d0229f34674

https://github.com/opnsense/core/security/advisories/GHSA-8pgr-x852-qx4j

https://hackerask.com/posts/opnsense

https://github.com/opnsense/core/security/advisories/GHSA-8pgr-x852-qx4j