CVE-2026-53582

HIGH
Published Oct 15, 2026 Modified Oct 15, 2026 CWE-91 CWE-643

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.

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CVSS v3.1 Score

7.1
HIGH
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:L

Weakness Type (CWE)

CWE-91 CWE-91
CWE-643 CWE-643

References

Frequently Asked Questions

What is CVE-2026-53582? +
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. It has a CVSS v3.1 base score of 7.1 (HIGH).
How severe is CVE-2026-53582? +
CVE-2026-53582 has a CVSS v3.1 score of 7.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
How do I check if I'm vulnerable to CVE-2026-53582? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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