CVE-2026-58392 Details
Description
OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the NTP GPS page stores the operator-supplied initcmd value in base64 form, applies legacy_html_escape_form_data() to the encoded string, and then uses base64_decode() to decode the value directly into the GPS initialization-command textarea in src/www/services_ntpd_gps.php. Because decoding occurs after escaping, stored HTML remains unescaped at the output sink. A user with page-services-ntp-gps privilege can store a value that closes the textarea, and script executes in the session of any user who later opens the GPS page. The script can read CSRF material and perform authenticated actions, including actions available to an administrator. This issue is fixed in version 26.1.11.
A stored cross-site scripting vulnerability has been identified in the OPNsense NTP GPS configuration page, affecting versions through 26.1.10 and 26.4.1. The issue arises because the 'initcmd' value, supplied by the user, is base64-encoded and then decoded directly into a textarea on the GPS page. This decoding process occurs after applying a legacy HTML escape, leaving the output unescaped and vulnerable to script injection. A user with the 'page-services-ntp-gps' privilege can exploit this by injecting a script that executes in the session of anyone who opens the GPS page, potentially leading to unauthorized actions, including those reserved for administrators.
Users can update to OPNsense version 26.1.11 or 26.4.1p1, both of which include the necessary fix for this vulnerability.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Oct 15, 2026CISA-ADP
Assessed Oct 15, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/opnsense/core/security/advisories/GHSA-h793-67jm-j4m5 | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/opnsense/core/commit/a92d9514b5436c868f8f97138ebed507f6de423c | [email protected] | Source CodeVendor |
| https://github.com/opnsense/core/commit/ed04a154dc40967541be1388e9134e451be4199e | [email protected] | Source CodeVendor |
| https://github.com/opnsense/core/security/advisories/GHSA-h793-67jm-j4m5 | [email protected] | AdvisoryExploitRemedyVendor |
| https://hackerask.com/posts/opnsense | [email protected] | BundleExploitRemedyTechnical Analysis |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-79 | Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| OPNsense | <= 26.1.10 (semver) <= 26.4.1 (semver) |
CPE
Remediation
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Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Oct 15, 2026 | New CVE Received | [email protected] |
| Oct 15, 2026 | CVE Modified | CISA-ADP |