CVE-2026-49825lxml: javascript: URL bypass in Cleaner via xlink:href
- 8.2HighCVSS base score
- 0.30%Exploitation in 30 daysEPSS · top 77% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
Timeline
ID reserved
By GitHub_M
- 3 months later
· 3 months later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N |
| NVDNVD · Awaiting Analysis | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.30% · top 77% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.2.
Affected products
- affected < 6.1.1
fedora-python · lxml_html_clean
- affected < 0.4.5
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPIlxml_html_cleanGHSA-4jhm-jv67-739f (opens in a new tab)
References
References5
- https://github.com/fedora-python/lxml_html_clean/security/advisories/GHSA-4jhm-jv67-739f (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/fedora-python/lxml_html_clean/commit/322357ac61c6cf80fcbaba53b4e92e31f3ded9f2 (opens in a new tab)x_refsource_MISC
- https://github.com/lxml/lxml/commit/5927a6d5e851845140975d99b65461e255caaab0 (opens in a new tab)x_refsource_MISC
- https://github.com/fedora-python/lxml_html_clean/releases/tag/0.4.5 (opens in a new tab)x_refsource_MISC
- https://github.com/lxml/lxml/releases/tag/lxml-6.1.1 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-63390 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-4jhm-jv67-739f (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-49825)Record last updated .