{"id":"CVE-2026-119423","state":"PUBLISHED","title":"OPNsense core before 26.7.8 Lockout IP Planting via WebGUI Login Username","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.","publishedAt":"2026-10-30T11:30:53.650Z","updatedAt":"2026-10-30T11:30:53.650Z","severity":{"score":6.9,"label":"Medium","version":"4.0","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","source":"VulnCheck"},"assigner":"VulnCheck","products":["opnsense core"],"affected":[{"vendor":"opnsense","product":"core","packageURL":"pkg:github/opnsense/core","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"26.7.8","versionType":"semver"}],"repo":"https://github.com/opnsense/core"}],"references":["https://github.com/opnsense/core/commit/14f8f7dd1d5f06522d60794a7beeac7adb9eca68","https://github.com/opnsense/core/commit/2076f2c195bf9537ec220f0e5d6aff998f057410","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/security/advisories/GHSA-2v2x-m4j7-76pv","https://abraxaslabs.tech/research/opnsense-lockout-factory-ip","https://github.com/opnsense/core","https://www.vulncheck.com/advisories/opnsense-core-before-26.7.8-lockout-ip-planting-via-webgui-login-username"],"weaknesses":["CWE-117"],"ingestedAt":"2026-10-30T11:38:06.457Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/119xxx/CVE-2026-119423.json","commit":"caad128d12b89565fbbe034f6027c5d022a3f402","baselineCommit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-119423","state":"PUBLISHED","datePublished":"2026-10-30T11:30:53.650Z","dateUpdated":"2026-10-30T11:30:53.650Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-10-30T02:41:13.241Z"},"containers":{"cna":{"title":"OPNsense core before 26.7.8 Lockout IP Planting via WebGUI Login Username","descriptions":[{"lang":"en","value":"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. 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