CVE-2026-53582

High

Description

OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.10, the Trust module stores attacker-controlled certificate authority and certificate refid values and interpolates them into XPath expressions in src/opnsense/mvc/app/models/OPNsense/Trust/FieldTypes/CAsField.php and src/opnsense/mvc/app/models/OPNsense/Trust/FieldTypes/CertificatesField.php. A user with CA Manager or Certificate Manager privileges can submit a crafted refid and repeatedly retrieve the object to obtain a boolean refcount oracle, allowing values in config.xml to be recovered character by character. Exposed values can include password hashes, API credentials, certificate private keys, VPN key material, and high-availability credentials, enabling privilege escalation and compromise of other security domains. This issue is fixed in version 26.1.10.

SeverityHigh
CVSS7.1
Exploit probability—
ProductOpnsense Core
PublishedOct 15, 2026
First seenOct 15, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
opnsense core< 26.1.10—

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