Description
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.
References5
Metrics
- CVSS 3.1
-
5.2
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:L/A:N - EPSS — exploit probability
- 0% percentile: 15 · as of 10 November 2026
- CWE
- CWE-79
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