lxml.html.defs.link_attrs were missing xlink:href · Prior to 6.1.1, link attributes
Affects lxmlSource GCVE Database
Not known to be exploited · CVSS 8.2 High · fixed in 3.3.3-1ubuntu0.2+esm6 : patch lxml soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.3.3-1ubuntu0.2+esm6, 3.5.0-1ubuntu0.4+esm3, 4.2.1-1ubuntu0.6+esm1 +4
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 20 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlxmlpkg:deb/ubuntu/lxml?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlxmlpkg:deb/ubuntu/lxml?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTSlxmlpkg:deb/ubuntu/lxml?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Ubuntu Pro 20.04 LTSlxmlpkg:deb/ubuntu/lxml?arch=source&distro=esm-infra/focalOther threats | Affected
| Fixed in
|
Ubuntu Pro 18.04 LTSlxmlpkg:deb/ubuntu/lxml?arch=source&distro=esm-infra/bionicOther threats | Affected
| Fixed in
|
Ubuntu Pro 16.04 LTSlxmlpkg:deb/ubuntu/lxml?arch=source&distro=esm-infra-legacy/xenialOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.