Loofah `allowed_uri?` does not detect `javascript:` URIs split by numeric character references without semicolons

{
  "id": "749d8cd14eeecffce752d5c7f55ca50457f4f144c63d4c05862a363180490e6e",
  "url": "https://osv.dev/vulnerability/CVE-2026-73492",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Loofah `allowed_uri?` does not detect `javascript:` URIs split by numeric character references without semicolons",
    "summary": "Loofah is a general library for manipulating and transforming HTML/XML documents and fragments, built on top of Nokogiri. From 2.25.0 until 2.25.2, Loofah::HTML5::Scrub.allowed_uri? does not reject javascript: or vbscript: URIs whose scheme is split by semicolon-less numeric character references such as :, , , or . CGI.unescapeHTML leaves these references encoded, so allowed_uri? reports the URL safe even though a browser decodes an encoded colon or strips encoded whitespace and executes the resulting URI scheme. This issue affects only callers that pass HTML-encoded strings directly to allowed_uri?; Loofah's default sanitize() path is not affected. This issue is fixed in version 2.25.2.",
    "evidence": "osv:CVE-2026-73492",
    "products": [],
    "severity": "low",
    "structured": {
      "id": "CVE-2026-73492",
      "aliases": [
        "CVE-2026-73492",
        "GHSA-5qhf-9phg-95m2"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/flavorjones/loofah",
              "type": "GIT",
              "events": [
                {
                  "introduced": "e65bdddfd3381f3a131be7e137d89bb3959c072b"
                },
                {
                  "fixed": "2706d7e858426ba856d9711b0e761b2fee7986c4"
                },
                {
                  "fixed": "f1be9d893b5a8dd79240441a912d8897e74c38c0"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "2.25.0"
                      },
                      {
                        "fixed": "2.25.2"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StringRangeExpression"
                  },
                  {
                    "range": [
                      {
                        "fixed": "f1be9d893b5a8dd79240441a912d8897e74c38c0"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "2706d7e858426ba856d9711b0e761b2fee7986c4"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "v2.25.2"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v2.25.1",
            "v2.25.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-73492.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:53.361101918Z",
      "provider": "osv",
      "references": [
        "https://github.com/flavorjones/loofah/releases/tag/v2.25.2",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73492.json",
        "https://github.com/flavorjones/loofah/security/advisories/GHSA-5qhf-9phg-95m2",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-73492",
        "https://github.com/flavorjones/loofah/commit/f1be9d893b5a8dd79240441a912d8897e74c38c0",
        "https://github.com/flavorjones/loofah/pull/308"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-184",
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73492.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-73492",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 522348,
  "published_at": "2026-08-12T21:00:24.679+00:00"
}