CVE-2026-119423
OPNsense core before 26.7.8 Lockout IP Planting via WebGUI Login Username
CVSS Score
5.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-117 |
| Vendor | opnsense |
| Product | core |
| Published | Oct 30, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low
Affected Versions
opnsense / core
0 < 26.7.8
References
github.com: https://github.com/opnsense/core/commit/14f8f7dd1d5f06522d60794a7beeac7adb9eca68 github.com: https://github.com/opnsense/core/commit/2076f2c195bf9537ec220f0e5d6aff998f057410 github.com: https://github.com/opnsense/core/blob/26.7.7/src/opnsense/mvc/app/library/OPNsense/Auth/AuthenticationFactory.php#L232 github.com: https://github.com/opnsense/core/blob/26.7.7/src/opnsense/scripts/syslog/lockout_handler#L70 github.com: https://github.com/opnsense/core/security/advisories/GHSA-2v2x-m4j7-76pv abraxaslabs.tech: https://abraxaslabs.tech/research/opnsense-lockout-factory-ip github.com: https://github.com/opnsense/core vulncheck.com: https://www.vulncheck.com/advisories/opnsense-core-before-26.7.8-lockout-ip-planting-via-webgui-login-username
Credits
Abraxas Labs Ad Schellevis