CVE-2026-119423 (GCVE-0-2026-119423)

Vulnerability from cvelistv5 – Published: 2026-10-30 11:30 – Updated: 2026-10-30 11:30
VLAI
Title
OPNsense core before 26.7.8 Lockout IP Planting via WebGUI Login Username
Summary
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.
Severity
6.9 (Medium)
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
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
  • CWE-117 - Improper Output Neutralization for Logs
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7155 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
opnsense core Affected: 0 , < 26.7.8 (semver)
    cpe:2.3:a:opnsense:opnsense:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-10-14 00:00
Credits
Abraxas Labs Ad Schellevis
Show details on NVD website
To clipboard 

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}



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