High
lxml: javascript: URL bypass in Cleaner via xlink:href
Type: advisorySources: OSV
lxml is a library for processing XML and HTML in the Python language. Prior to 6.1.1, link attributes in ``lxml.html.defs.link_attrs`` were missing ``xlink:href``, which can be used for URL bypass attacks in embedded SVG/MathML/etc. content. This vulnerability was fixed in lxml 6.1.1 and lxml_html_clean 0.4.5.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-49825
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 15:03 UTC · Revision 1
Source evidence
lxml: javascript: URL bypass in Cleaner via xlink:href
core-osv · Original sourcePublished 20 Aug 2026, 14:42 UTC
lxml is a library for processing XML and HTML in the Python language. Prior to 6.1.1, link attributes in ``lxml.html.defs.link_attrs`` were missing ``xlink:href``, which can be used for URL bypass attacks in embedded SVG/MathML/etc. content. This vulnerability was fixed in lxml 6.1.1 and lxml_html_clean 0.4.5.
osv:CVE-2026-49825
Complete source record
{
"id": "c2c1f23aeb10c95761c7d81bbfd060f95395c76f0ca50900cb0fba60c0864716",
"url": "https://osv.dev/vulnerability/CVE-2026-49825",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "lxml: javascript: URL bypass in Cleaner via xlink:href",
"summary": "lxml is a library for processing XML and HTML in the Python language. Prior to 6.1.1, link attributes in ``lxml.html.defs.link_attrs`` were missing ``xlink:href``, which can be used for URL bypass attacks in embedded SVG/MathML/etc. content. This vulnerability was fixed in lxml 6.1.1 and lxml_html_clean 0.4.5.",
"evidence": "osv:CVE-2026-49825",
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"GHSA-4jhm-jv67-739f",
"PYSEC-2026-2614"
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"modified": "2026-10-28T02:30:29.991263437Z",
"provider": "osv",
"references": [
"https://github.com/fedora-python/lxml_html_clean/releases/tag/0.4.5",
"https://github.com/lxml/lxml/releases/tag/lxml-6.1.1",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49825.json",
"https://github.com/fedora-python/lxml_html_clean/security/advisories/GHSA-4jhm-jv67-739f",
"https://nvd.nist.gov/vuln/detail/CVE-2026-49825",
"https://github.com/fedora-python/lxml_html_clean/commit/322357ac61c6cf80fcbaba53b4e92e31f3ded9f2",
"https://github.com/lxml/lxml/commit/5927a6d5e851845140975d99b65461e255caaab0"
],
"provider_metadata": {
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"cna_assigner": "GitHub_M",
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}
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"evidence": "/id"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 496632,
"published_at": "2026-08-20T14:42:30.748+00:00"
}