CVE-2024-52595: Lxml html clean HTML Cleaner Allows Crafted Scripts Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-5jfw-gq64-q45f",
  "modified" : "2025-01-14T16:37:30Z",
  "published" : "2024-11-19T21:07:59Z",
  "aliases" : [ "CVE-2024-52595" ],
  "summary" : "HTML Cleaner allows crafted scripts in special contexts like svg or math to pass through",
  "details" : "### Impact\n\nThe HTML Parser in lxml does not properly handle context-switching for special HTML tags such as `<svg>`, `<math>` and `<noscript>`. This behavior deviates from how web browsers parse and interpret such tags. Specifically, content in CSS comments is ignored by lxml_html_clean but may be interpreted differently by web browsers, enabling malicious scripts to bypass the cleaning process. This vulnerability could lead to Cross-Site Scripting (XSS) attacks, compromising the security of users relying on lxml_html_clean in default configuration for sanitizing untrusted HTML content.\n\n### Patches\n\nUsers employing the HTML cleaner in a security-sensitive context should upgrade to lxml 0.4.0, which addresses this issue.\n\n### Workarounds\n\nAs a temporary mitigation, users can configure lxml_html_clean with the following settings to prevent the exploitation of this vulnerability:\n* `remove_tags`: Specify tags to remove - their content is moved to their parents' tags.\n* `kill_tags`: Specify tags to be removed completely.\n* `allow_tags`: Restrict the set of permissible tags, excluding context-switching tags like `<svg>`, `<math>` and `<noscript>`.\n\n### References\n\n* https://github.com/fedora-python/lxml_html_clean/pull/19\n* https://github.com/fedora-python/lxml_html_clean/pull/19/commits/c5d816f86eb3707d72a8ecf5f3823e0daa1b3808\n",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "lxml-html-clean"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.4.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/fedora-python/lxml_html_clean/security/advisories/GHSA-5jfw-gq64-q45f"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2024-52595"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/fedora-python/lxml_html_clean/pull/19"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/fedora-python/lxml_html_clean/commit/c5d816f86eb3707d72a8ecf5f3823e0daa1b3808"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/fedora-python/lxml_html_clean"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/lxml-html-clean/PYSEC-2024-160.yaml"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-184", "CWE-79", "CWE-83" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2024-11-19T21:07:59Z",
    "nvd_published_at" : "2024-11-19T22:15:21Z"
  }
}