{"id":"UBUNTU-CVE-2026-126079","details":"Action View is a framework for handling view template lookup and rendering and provides view helpers for building HTML. Prior to 8.1.4.1 and 8.0.5.2, with the HTML5 sanitizer (Rails::HTML5::Sanitizer, the default vendor on CRuby for applications using load_defaults 7.1 or later), Nokogiri before 1.19.5 serializes \u003c and \u003e unescaped inside attribute values. The Action View text helpers highlight and simple_format sanitize their input and then process the resulting HTML as a string: highlight splits it on tag boundaries to insert matches, and simple_format splits it into paragraphs on blank lines. An unescaped \u003e or a blank line inside an attribute value could cause markup in that value, which the sanitizer left inert, to be emitted as live elements in the helper's html_safe output, possibly leading to XSS. Applications that use the HTML5 sanitizer and pass untrusted text to highlight, or to simple_format with html_options, are affected. This issue is fixed in versions 8.1.4.1 and 8.0.5.2.","modified":"2026-11-12T23:46:37.624773237Z","published":"2026-11-12T00:00:00Z","upstream":["CVE-2026-126079"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-126079"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-126079"},{"type":"REPORT","url":"https://github.com/rails/rails/security/advisories/GHSA-2p2f-4rq4-gjwc"},{"type":"REPORT","url":"http://github.com/rails/rails/commit/adc3a32d4abea77ed3aacf6f5fb71cfc005bef73"},{"type":"REPORT","url":"https://github.com/rails/rails/commit/009ea68342d05d02087c04dae7faaa4e4c1def11"},{"type":"REPORT","url":"https://github.com/rails/rails/releases/tag/v8.0.5.2"},{"type":"REPORT","url":"https://github.com/rails/rails/releases/tag/v8.1.4.1"}],"affected":[{"package":{"name":"rails","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/rails?arch=source&distro=esm-apps%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2:4.1.10-1","2:4.2.5-1","2:4.2.5.1-1","2:4.2.5.2-2","2:4.2.6-1","2:4.2.6-1ubuntu0.1~esm1","2:4.2.6-1ubuntu0.1~esm2"],"ecosystem_specific":{"binaries":[{"binary_version":"2:4.2.6-1ubuntu0.1~esm2","binary_name":"rails"},{"binary_name":"ruby-actionmailer","binary_version":"2:4.2.6-1ubuntu0.1~esm2"},{"binary_name":"ruby-actionpack","binary_version":"2:4.2.6-1ubuntu0.1~esm2"},{"binary_name":"ruby-actionview","binary_version":"2:4.2.6-1ubuntu0.1~esm2"},{"binary_name":"ruby-activejob","binary_version":"2:4.2.6-1ubuntu0.1~esm2"},{"binary_version":"2:4.2.6-1ubuntu0.1~esm2","binary_name":"ruby-activemodel"},{"binary_name":"ruby-activerecord","binary_version":"2:4.2.6-1ubuntu0.1~esm2"},{"binary_version":"2:4.2.6-1ubuntu0.1~esm2","binary_name":"ruby-activesupport"},{"binary_name":"ruby-rails","binary_version":"2:4.2.6-1ubuntu0.1~esm2"},{"binary_name":"ruby-railties","binary_version":"2:4.2.6-1ubuntu0.1~esm2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-126079.json"}},{"package":{"name":"rails","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/rails?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2:4.2.9-2","2:4.2.9-4","2:4.2.10-0ubuntu4","2:4.2.10-0ubuntu4+esm1","2:4.2.10-0ubuntu4+esm2"],"ecosystem_specific":{"binaries":[{"binary_name":"rails","binary_version":"2:4.2.10-0ubuntu4+esm2"},{"binary_name":"ruby-actionmailer","binary_version":"2:4.2.10-0ubuntu4+esm2"},{"binary_name":"ruby-actionpack","binary_version":"2:4.2.10-0ubuntu4+esm2"},{"binary_version":"2:4.2.10-0ubuntu4+esm2","binary_name":"ruby-actionview"},{"binary_name":"ruby-activejob","binary_version":"2:4.2.10-0ubuntu4+esm2"},{"binary_name":"ruby-activemodel","binary_version":"2:4.2.10-0ubuntu4+esm2"},{"binary_version":"2:4.2.10-0ubuntu4+esm2","binary_name":"ruby-activerecord"},{"binary_name":"ruby-activesupport","binary_version":"2:4.2.10-0ubuntu4+esm2"},{"binary_name":"ruby-rails","binary_version":"2:4.2.10-0ubuntu4+esm2"},{"binary_name":"ruby-railties","binary_version":"2:4.2.10-0ubuntu4+esm2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-126079.json"}},{"package":{"name":"rails","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/rails?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2:5.2.2.1+dfsg-1ubuntu1","2:5.2.3+dfsg-3","2:5.2.3+dfsg-3ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"rails","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_name":"ruby-actioncable","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_name":"ruby-actionmailer","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1","binary_name":"ruby-actionpack"},{"binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1","binary_name":"ruby-actionview"},{"binary_name":"ruby-activejob","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_name":"ruby-activemodel","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_name":"ruby-activerecord","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_name":"ruby-activestorage","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1","binary_name":"ruby-activesupport"},{"binary_name":"ruby-rails","binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1"},{"binary_version":"2:5.2.3+dfsg-3ubuntu0.1~esm1","binary_name":"ruby-railties"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-126079.json"}},{"package":{"name":"rails","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/rails?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2:6.0.3.7+dfsg-2","2:6.1.4.1+dfsg-8ubuntu2","2:6.1.4.1+dfsg-8ubuntu2+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"rails","binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1"},{"binary_name":"ruby-actioncable","binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1"},{"binary_name":"ruby-actionmailbox","binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1"},{"binary_name":"ruby-actionmailer","binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1"},{"binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1","binary_name":"ruby-actionpack"},{"binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1","binary_name":"ruby-actiontext"},{"binary_name":"ruby-actionview","binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1"},{"binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1","binary_name":"ruby-activejob"},{"binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1","binary_name":"ruby-activemodel"},{"binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1","binary_name":"ruby-activerecord"},{"binary_name":"ruby-activestorage","binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1"},{"binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1","binary_name":"ruby-activesupport"},{"binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1","binary_name":"ruby-rails"},{"binary_name":"ruby-railties","binary_version":"2:6.1.4.1+dfsg-8ubuntu2+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-126079.json"}},{"package":{"name":"rails","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/rails?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2:6.1.7.3+dfsg-2build1","2:6.1.7.3+dfsg-3"],"ecosystem_specific":{"binaries":[{"binary_name":"rails","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_version":"2:6.1.7.3+dfsg-3","binary_name":"ruby-actioncable"},{"binary_name":"ruby-actionmailbox","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_name":"ruby-actionmailer","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_name":"ruby-actionpack","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_version":"2:6.1.7.3+dfsg-3","binary_name":"ruby-actiontext"},{"binary_version":"2:6.1.7.3+dfsg-3","binary_name":"ruby-actionview"},{"binary_name":"ruby-activejob","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_version":"2:6.1.7.3+dfsg-3","binary_name":"ruby-activemodel"},{"binary_name":"ruby-activerecord","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_name":"ruby-activestorage","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_version":"2:6.1.7.3+dfsg-3","binary_name":"ruby-activesupport"},{"binary_name":"ruby-rails","binary_version":"2:6.1.7.3+dfsg-3"},{"binary_name":"ruby-railties","binary_version":"2:6.1.7.3+dfsg-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-126079.json"}},{"package":{"name":"rails","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/rails?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2:7.2.3+dfsg-2","2:7.2.3.2+dfsg-2"],"ecosystem_specific":{"binaries":[{"binary_name":"rails","binary_version":"2:7.2.3.2+dfsg-2"},{"binary_name":"ruby-actioncable","binary_version":"2:7.2.3.2+dfsg-2"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-actionmailbox"},{"binary_name":"ruby-actionmailer","binary_version":"2:7.2.3.2+dfsg-2"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-actionpack"},{"binary_name":"ruby-actiontext","binary_version":"2:7.2.3.2+dfsg-2"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-actionview"},{"binary_name":"ruby-activejob","binary_version":"2:7.2.3.2+dfsg-2"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-activemodel"},{"binary_name":"ruby-activerecord","binary_version":"2:7.2.3.2+dfsg-2"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-activestorage"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-activesupport"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-rails"},{"binary_version":"2:7.2.3.2+dfsg-2","binary_name":"ruby-railties"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-126079.json"}},{"package":{"name":"rails","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/rails?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2:7.2.2.1+dfsg-7","2:7.2.2.2+dfsg-2","2:7.2.3+dfsg-2"],"ecosystem_specific":{"binaries":[{"binary_version":"2:7.2.3+dfsg-2","binary_name":"rails"},{"binary_name":"ruby-actioncable","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-actionmailbox","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-actionmailer","binary_version":"2:7.2.3+dfsg-2"},{"binary_version":"2:7.2.3+dfsg-2","binary_name":"ruby-actionpack"},{"binary_name":"ruby-actiontext","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-actionview","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-activejob","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-activemodel","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-activerecord","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-activestorage","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-activesupport","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-rails","binary_version":"2:7.2.3+dfsg-2"},{"binary_name":"ruby-railties","binary_version":"2:7.2.3+dfsg-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-126079.json"}}],"schema_version":"1.9.2","severity":[{"type":"Ubuntu","score":"medium"}]}