{"id":"CVE-2026-126079","summary":"Action View: Possible XSS vulnerability in Action View text helpers","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.","aliases":["GHSA-2p2f-4rq4-gjwc"],"modified":"2026-11-11T10:47:26.588587736Z","published":"2026-11-10T21:02:30.667Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-79"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126079.json"},"references":[{"type":"FIX","url":"http://github.com/rails/rails/commit/adc3a32d4abea77ed3aacf6f5fb71cfc005bef73"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/126xxx/CVE-2026-126079.json"},{"type":"FIX","url":"https://github.com/rails/rails/commit/009ea68342d05d02087c04dae7faaa4e4c1def11"},{"type":"WEB","url":"https://github.com/rails/rails/releases/tag/v8.0.5.2"},{"type":"WEB","url":"https://github.com/rails/rails/releases/tag/v8.1.4.1"},{"type":"ADVISORY","url":"https://github.com/rails/rails/security/advisories/GHSA-2p2f-4rq4-gjwc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-126079"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/rails/rails","events":[{"introduced":"0"},{"fixed":"235c597b100321b6bd2d62f8df63707f42b25b2d"},{"introduced":"1cdd190a25e483b65f1f25bbd0f13a25d696b461"},{"fixed":"3f290b759c8e2ffe7c257951b1255740751355e4"},{"fixed":"009ea68342d05d02087c04dae7faaa4e4c1def11"},{"fixed":"adc3a32d4abea77ed3aacf6f5fb71cfc005bef73"}],"database_specific":{"extracted_events":[{"strategy":"StringRangeExpression","range":[{"introduced":"0"},{"fixed":"8.0.5.2"}],"source":"AFFECTED_FIELD"},{"strategy":"StringRangeExpression","range":[{"introduced":"8.1"},{"fixed":"8.1.4.1"}],"source":"AFFECTED_FIELD"},{"range":[{"fixed":"009ea68342d05d02087c04dae7faaa4e4c1def11"}],"source":"REFERENCES_COMMIT"},{"range":[{"fixed":"235c597b100321b6bd2d62f8df63707f42b25b2d"}],"source":"REFERENCES_TAG","original_tag":"v8.0.5.2"},{"original_tag":"v8.1.4.1","range":[{"fixed":"3f290b759c8e2ffe7c257951b1255740751355e4"}],"source":"REFERENCES_TAG"},{"source":"REFERENCES_COMMIT","range":[{"fixed":"adc3a32d4abea77ed3aacf6f5fb71cfc005bef73"}]}]}}],"versions":["v8.0.5.1","v8.1.4","v8.0.5","v8.1.3","v8.0.4","v8.1.2","v8.1.1","v8.1.0","v8.0.3","v8.0.2","v8.0.1","v8.0.0","v8.0.0.rc2","v8.0.0.rc1","v8.0.0.beta1","v7.1.0.beta1","v7.0.0.alpha2","v7.0.0.alpha1","v6.1.0.rc1","v6.0.0.beta2","v6.0.0.beta1","v5.1.0.beta1","v5.0.0.beta4","v5.0.0.beta2","v5.0.0.beta1","v4.2.0.beta1","v4.0.0.rc1","v4.0.0.beta1","v3.2.0.rc1","v3.1.0.rc1","v3.1.0.beta1","v3.0.0.beta3","v3.0.0.beta.3","v2.0.1","v2.0.0","v2.0.0_RC2","v2.0.0_RC1","v2.0.0_PR","v1.1.1","v1.1.0","v1.1.0_RC1","v0.14.3","v0.14.1","v0.13.1","v0.13.0","v0.12.0","v0.11.1","v0.11.0","v0.10.1","v0.10.0","v0.9.5","v0.9.4.1","v0.9.4","v0.9.3","v0.9.2","v0.9.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-126079.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"}]}