CVE-2026-119423

OPNsense core before 26.7.8 Lockout IP Planting via WebGUI Login Username

Published Oct 30, 2026 CVSS 4.0 · 6.9 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Opnsense core
Vendors & Products Opnsense core
Type Values Removed Values Added
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.
Title OPNsense core before 26.7.8 Lockout IP Planting via WebGUI Login Username
First Time appeared Opnsense
Opnsense opnsense
Weaknesses CWE-117
CPEs cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*
Vendors & Products Opnsense
Opnsense opnsense
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Nov 4, 2026, 3:05 PM
Reserved
Oct 30, 2026, 2:41 AM
Status
Awaiting Analysis
Published
Oct 30, 2026, 12:16 PM
Modified
Nov 4, 2026, 3:17 PM