CVE-2026-119423

Description

OPNsense core before 26.7.8 contains a log injection vulnerability that allows unauthenticated attackers to plant victim IP addresses in the lockout_handler by submitting crafted WebGUI login usernames. Attackers can submit usernames like 'Invalid user <victim-ip>' repeatedly to add the victim to the sshlockout table, blocking SSH and WebGUI access and killing its pf states.

References

• https://abraxaslabs.tech/research/opnsense-lockout-factory-ip
• https://github.com/opnsense/core
• https://github.com/opnsense/core/blob/26.7.7/src/opnsense/mvc/app/library/OPNsense/Auth/AuthenticationFactory.php#L232
• https://github.com/opnsense/core/blob/26.7.7/src/opnsense/scripts/syslog/lockout_handler#L70
• https://github.com/opnsense/core/commit/14f8f7dd1d5f06522d60794a7beeac7adb9eca68