CVE-2026-58395: OPNsense: XPath injection in MVC safe-delete
OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the safe-delete path reached through ApiMutableModelControllerBase::delBase() interpolates an unvalidated safe-delete token from the request URL into an XPath expression over config.xml before confirming that the token is a valid identifier. A user holding any one affected module privilege can send a crafted token to one of 21 affected delete endpoints covering Traffic Shaper, DHCP relay, Dnsmasq, Firewall Category, or Kea DHCP, causing the XPath to match configuration data across modules. The resulting error response exposes configuration item names, descriptions, reference paths, and UUIDs and provides an XPath substring-presence oracle, including for modules the user cannot otherwise access. The request does not modify configuration or perform a deletion. This issue is fixed in version 26.1.11.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
OPNsenseto a version that resolves this vulnerability.Fixed in 26.1.11
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker needs an authenticated account with any one affected module privilege. The flaw can then be reached through one of 21 affected delete endpoints associated with Traffic Shaper, DHCP relay, Dnsmasq, Firewall Category, or Kea DHCP.
What information can be exposed?
Crafted safe-delete tokens can cause XPath matches across configuration modules, including modules the user is not authorized to access. Error responses can disclose configuration item names, descriptions, reference paths, and UUIDs, and act as an XPath substring-presence oracle.
Does exploitation alter or delete configuration?
No. The crafted request does not modify configuration and does not perform a deletion; its impact is information disclosure.
What is the remediation?
Upgrade OPNsense to version 26.1.11, which fixes the issue.