CVE Catalog

CVE-2026-63442

HighCVSS 8.1
Published: Translated: NVD NIST

Summary

OPNsense, a FreeBSD-based firewall and routing platform, prior to 26.1.11 allows carriage-return and line-feed characters in the WebGUI login username field. An attacker with network access to the login page can forge authentication events for another IP, adding it to the sshlockout PF table, or reset their own brute-force counter.

Risk Assessment

Administrative, DNS, gateway, or monitoring addresses can be blocked, and password-guessing lockout can be bypassed without authentication.

Recommendation

Update OPNsense to version 26.1.11 or later.

Other vulnerabilities in OPNsense

See all
Original NVD description (English source)

OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the unauthenticated WebGUI login usernamefld accepts carriage-return and line-feed characters that survive LOG_AUTH processing through syslog-ng-lockout.conf into the syslog-ng program destination feeding lockout_handler. The consumer's readline() processing treats an injected fragment as a separate authentication event and selects the first syntactically valid IP address from the forged line. An attacker with network access to the login page can forge failure events for another IP, causing that IP to be added to the sshlockout PF table and its active states to be killed, or forge accepted events that reset an attacker's own brute-force counter. This can block administrative, DNS, gateway, or monitoring addresses and can bypass password-guessing lockout without authentication. This issue is fixed in version 26.1.11.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS