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://www.vulncheck.com/advisories/opnsense-core-before-26.7.8-lockout-ip-planting-via-webgui-login-username

https://github.com/opnsense/core/security/advisories/GHSA-2v2x-m4j7-76pv

https://github.com/opnsense/core/commit/2076f2c195bf9537ec220f0e5d6aff998f057410

https://github.com/opnsense/core/commit/14f8f7dd1d5f06522d60794a7beeac7adb9eca68

https://github.com/opnsense/core/blob/26.7.7/src/opnsense/scripts/syslog/lockout_handler#L70

https://github.com/opnsense/core/blob/26.7.7/src/opnsense/mvc/app/library/OPNsense/Auth/AuthenticationFactory.php#L232

https://github.com/opnsense/core

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-113803

https://abraxaslabs.tech/research/opnsense-lockout-factory-ip

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4

EPSS