{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.5.0"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "8033a5c690af9c2c443f58e34875343fa4cc1d07"
            },
            {
              "fixed": "868a3d2f10e191c72e7adc32972e185cce652356"
            }
          ],
          "repo": "https://github.com/anglesharp/anglesharp",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-pgww-w46g-26qg"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-80"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54570.json"
  },
  "details": "AngleSharp is a .NET library for parsing angle bracket based hyper-texts. Prior to 1.5.0, MathAnnotationXmlElement in AngleSharp/Mathml/Dom/Internal/MathAnnotationXmlElement.cs is not treated as an HTML integration point when its encoding attribute is text/html or application/xhtml+xml, causing Consume in AngleSharp/Html/Parser/HtmlDomBuilder.cs to route tokens through foreign-content parsing instead of HTML parsing. A sanitizer can therefore observe a different DOM from the browser that reparses the serialized output. An attacker can combine this namespace differential with markup-breaking characters in an attribute value so that an element hidden from the sanitizer becomes active script-capable HTML after browser reparse, resulting in mutation cross-site scripting. This issue is fixed in version 1.5.0.",
  "id": "CVE-2026-54570",
  "modified": "2026-09-20T11:30:55.356749312Z",
  "published": "2026-08-18T17:39:51.827Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/AngleSharp/AngleSharp/releases/tag/1.5.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/AngleSharp/AngleSharp/security/advisories/GHSA-pgww-w46g-26qg"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54570.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54570"
    },
    {
      "type": "FIX",
      "url": "https://github.com/AngleSharp/AngleSharp/commit/8033a5c690af9c2c443f58e34875343fa4cc1d07"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "AngleSharp: HTML5 Spec Compliance: mXSS via annotation-xml HTML Integration Point Bypass"
}