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TI-2026-36731 Aliases CVE-2026-49825GHSA-4jhm-jv67-739f

lxml: javascript: URL bypass in Cleaner via xlink:href

Priority HIGH 69CWE-184Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Cross-site scripting
Confidentiality · integrity · availability
High · Low · None
Fix status
Partial Red Hat: 29 fixed, 16 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-79.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00297 22nd percentileScored 2026-11-07
Fix Partial lxml (lxml): 6.1.1lxml_html_clean (fedora-python): 0.4.5+1 more productRed Hat: 29 advisoriesRed Hat: 29 fixed, 16 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
lxmllxmlbefore 6.1.16.1.1Patch availableCNA
fedora-pythonlxml_html_cleanbefore 0.4.50.4.5Patch availableCNA
—lxml_html_clean (PyPI)before 0.4.50.4.5Patch availableGHSA-4jhm-jv67-739f
  • lxml Vendorlxml Affected before 6.1.1 Fixed in 6.1.1 Patch available CNA
  • lxml_html_clean Vendorfedora-python Affected before 0.4.5 Fixed in 0.4.5 Patch available CNA
  • lxml_html_clean (PyPI) Vendor— Affected before 0.4.5 Fixed in 0.4.5 Patch available GHSA-4jhm-jv67-739f

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:fedoralovespython:lxml_html_clean:*:*:*:*:*:*:*:*——fedora-python
  • cpe:2.3:a:fedoralovespython:lxml_html_clean:*:*:*:*:*:*:*:* Versions — — ·fedora-python

Remediation

  • Fix · CNA lxml (lxml) Fixed in 6.1.1
  • Fix · CNA lxml_html_clean (fedora-python) Fixed in 0.4.5
  • Fix · GHSA-4jhm-jv67-739f lxml_html_clean (PyPI) Fixed in 0.4.5 Advisory →

Red Hat 29 advisories

  • RHSA-2026:90336 Released 2026-10-26 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION) python-lxml-2.2.3-1.2.el6_10
  • RHSA-2026:90327 Released 2026-10-26 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) python-lxml-3.2.1-4.el7_9.1
    • Red Hat Enterprise Linux Server Optional (v. 7 ELS) python-lxml-docs-3.2.1-4.el7_9.1
  • RHSA-2026:90326 Released 2026-10-26 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) python-lxml-4.2.3-2.el8_4.1, python3-lxml-4.2.3-2.el8_4.1
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) python-lxml-4.2.3-2.el8_4.1, python3-lxml-4.2.3-2.el8_4.1
Show 26 more Red Hat advisories
  • RHSA-2026:87410 Released 2026-10-21 · Red Hat rating Critical
    RHOAI 2.25.12 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-caikit-nlp-rhel9, registry.redhat.io/rhoai/odh-codeflare-operator-rhel9 +47
  • RHSA-2026:86891 Released 2026-10-21 · Red Hat rating Critical
    RHOAI 3.5.2 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.5 registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-cli-rhel9 +47
  • RHSA-2026:84734 Released 2026-10-19 · Red Hat rating Critical
    RHOAI 3.4.5 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.4 registry.redhat.io/rhoai/odh-ai-gateway-payload-processing-rhel9, registry.redhat.io/rhoai/odh-automl-rhel9, registry.redhat.io/rhoai/odh-autorag-rhel9 +47
  • RHSA-2026:84593 Released 2026-10-19 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) python-lxml-4.2.3-4.el8_8.1, python3-lxml-4.2.3-4.el8_8.1
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) python-lxml-4.2.3-4.el8_8.1, python3-lxml-4.2.3-4.el8_8.1
  • RHSA-2026:84592 Released 2026-10-19 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) python-lxml-4.2.3-4.el8_6.1, python3-lxml-4.2.3-4.el8_6.1
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) python-lxml-4.2.3-4.el8_6.1, python3-lxml-4.2.3-4.el8_6.1
  • RHSA-2026:81110 Released 2026-10-12 · Red Hat rating Important
    Red Hat Quay 3.18.1
    • Red Hat Quay 3.18 registry.redhat.io/quay/quay-builder-rhel9, registry.redhat.io/quay/quay-rhel9
  • RHSA-2026:79546 Released 2026-10-08 · Red Hat rating Important
    Red Hat Quay 3.12.23
    • Red Hat Quay 3.12 registry.redhat.io/quay/quay-rhel8
  • RHSA-2026:79366 Released 2026-10-08 · Red Hat rating Important
    Red Hat Quay 3.10.27
    • Red Hat Quay 3.10 registry.redhat.io/quay/quay-rhel8
  • RHSA-2026:77656 Released 2026-10-07 · Red Hat rating Important
    Red Hat Quay 3.9.27
    • Red Hat Quay 3.9 registry.redhat.io/quay/quay-rhel8
  • RHSA-2026:74506 Released 2026-10-01 · Red Hat rating Critical
    Satellite 6.16.14 Async Update
    • Red Hat Satellite 6.16 for RHEL 8 foreman-3.12.0.23-1.el8sat, foreman-cli-3.12.0.23-1.el8sat, foreman-debug-3.12.0.23-1.el8sat +32
    • Red Hat Satellite 6.16 for RHEL 9 foreman-3.12.0.23-1.el9sat, foreman-cli-3.12.0.23-1.el9sat, foreman-debug-3.12.0.23-1.el9sat +32
  • RHSA-2026:74505 Released 2026-10-01 · Red Hat rating Critical
    Satellite 6.17.12 Async Update
    • Red Hat Satellite 6.17 for RHEL 9 foreman-3.14.0.22-1.el9sat, foreman-cli-3.14.0.22-1.el9sat, foreman-debug-3.14.0.22-1.el9sat +31
  • RHSA-2026:74511 Released 2026-10-01 · Red Hat rating Important
    Red Hat Quay 3.17.5
    • Red Hat Quay 3.17 registry.redhat.io/quay/quay-rhel9
  • RHSA-2026:74081 Released 2026-09-30 · Red Hat rating Important
    python3.12-lxml security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) python3.12-lxml-4.9.3-2.el9_6.1
  • RHSA-2026:74082 Released 2026-09-30 · Red Hat rating Important
    python3.12-lxml security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) python3.12-lxml-4.9.3-2.el9_4.1
  • RHSA-2026:71210 Released 2026-09-23 · Red Hat rating Critical
    Red Hat Ansible Automation Platform 2.5 Container Release Update
    • Red Hat Ansible Automation Platform 2.5 registry.redhat.io/ansible-automation-platform-25/controller-rhel8, registry.redhat.io/ansible-automation-platform-25/de-minimal-rhel8, registry.redhat.io/ansible-automation-platform-25/ee-minimal-rhel8 +4
  • RHSA-2026:71192 Released 2026-09-23 · Red Hat rating Important
    Red Hat Ansible Automation Platform 2.5 Container Release Update
    • Red Hat Ansible Automation Platform 2.5 registry.redhat.io/ansible-automation-platform-25/de-minimal-rhel9, registry.redhat.io/ansible-automation-platform-25/ee-minimal-rhel9, registry.redhat.io/ansible-automation-platform-25/ee-supported-rhel9
  • RHSA-2026:71179 Released 2026-09-23 · Red Hat rating Critical
    Red Hat Ansible Automation Platform 2.6 Container Release Update
    • Red Hat Ansible Automation Platform 2.6 registry.redhat.io/ansible-automation-platform-26/aap-must-gather-rhel9, registry.redhat.io/ansible-automation-platform-26/controller-rhel9, registry.redhat.io/ansible-automation-platform-26/de-minimal-rhel9 +10
  • RHSA-2026:71177 Released 2026-09-23 · Red Hat rating Critical
    Red Hat Ansible Automation Platform 2.7 Container Release Update
    • Red Hat Ansible Automation Platform 2.7 registry.redhat.io/ansible-automation-platform-27/aap-must-gather-rhel9, registry.redhat.io/ansible-automation-platform-27/controller-rhel9, registry.redhat.io/ansible-automation-platform-27/de-minimal-rhel9 +4
  • RHSA-2026:67943 Released 2026-09-16 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream (v. 8) python-lxml-4.2.3-5.el8_10, python3-lxml-4.2.3-5.el8_10
  • RHSA-2026:67956 Released 2026-09-16 · Red Hat rating Important
    Red Hat Update Infrastructure 5.3 security update
    • Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-kubernetes-rhel9, registry.redhat.io/rhui5/cds-rhel9, registry.redhat.io/rhui5/haproxy-rhel9 +2
  • RHSA-2026:67324 Released 2026-09-14 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) python-lxml-4.6.5-3.el9_6.1, python3-lxml-4.6.5-3.el9_6.1
  • RHSA-2026:67325 Released 2026-09-14 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) python-lxml-4.6.5-3.el9_4.1, python3-lxml-4.6.5-3.el9_4.1
  • RHSA-2026:67326 Released 2026-09-14 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) python-lxml-4.6.5-3.el9_2.1, python3-lxml-4.6.5-3.el9_2.1
  • RHSA-2026:67279 Released 2026-09-14 · Red Hat rating Critical
    Red Hat Ansible Automation Platform 2.7 Container Release Update
    • Red Hat Ansible Automation Platform 2.7 registry.redhat.io/ansible-automation-platform-27/controller-rhel9, registry.redhat.io/ansible-automation-platform-27/eda-controller-rhel9, registry.redhat.io/ansible-automation-platform-27/ee-minimal-rhel9 +7
  • RHSA-2026:66204 Released 2026-09-09 · Red Hat rating Important
    python-lxml security update
    • Red Hat Enterprise Linux AppStream (v. 9) python-lxml-4.6.5-3.el9_8.1, python3-lxml-4.6.5-3.el9_8.1
  • RHSA-2026:66203 Released 2026-09-09 · Red Hat rating Important
    python3.12-lxml security update
    • Red Hat Enterprise Linux AppStream (v. 9) python3.12-lxml-4.9.3-2.el9_8.1

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Lightspeed CoreAffectedNo fix yet
Red Hat AI Inference ServerAffectedNo fix planned: Will not fix
Red Hat Ansible Automation Platform 2AffectedNo fix planned: Will not fix
Red Hat Ansible Automation Platform Ansible Core 2AffectedNo fix yet
Red Hat Ceph Storage 7AffectedNo fix yet: Fix deferred
Red Hat Ceph Storage 8AffectedNo fix yet: Fix deferred
Red Hat Ceph Storage 9AffectedNo fix yet: Fix deferred
Red Hat Certification Program for Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Red Hat OpenStack Platform 16.2AffectedNo fix yet
Red Hat OpenStack Platform 18.0AffectedNo fix yet
Red Hat Satellite 6AffectedNo fix yet
Red Hat Update Infrastructure 4 for Cloud ProvidersAffectedNo fix planned: Will not fix
Red Hat Update Infrastructure 5AffectedNo fix planned: Will not fix
Red Hat Ansible Automation Platform 2.5Fixed RHSA-2026:71192, RHSA-2026:71210
Red Hat Ansible Automation Platform 2.6Fixed RHSA-2026:71179
Red Hat Ansible Automation Platform 2.7Fixed RHSA-2026:67279, RHSA-2026:71177
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:67943
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:66203, RHSA-2026:66204
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:90326
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:84592
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:84593
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:67326
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:67325, RHSA-2026:74082
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:67324, RHSA-2026:74081
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:90326
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:84592
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:84593
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:90327
Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION)Fixed RHSA-2026:90336
Red Hat Enterprise Linux Server Optional (v. 7 ELS)Fixed RHSA-2026:90327
Red Hat OpenShift AI 2.25Fixed RHSA-2026:87410
Red Hat OpenShift AI 3.4Fixed RHSA-2026:84734
Red Hat OpenShift AI 3.5Fixed RHSA-2026:86891
Red Hat Quay 3.10Fixed RHSA-2026:79366
Red Hat Quay 3.12Fixed RHSA-2026:79546
Red Hat Quay 3.17Fixed RHSA-2026:74511
Red Hat Quay 3.18Fixed RHSA-2026:81110
Red Hat Quay 3.9Fixed RHSA-2026:77656
Red Hat Satellite 6.16 for RHEL 8Fixed RHSA-2026:74506
Red Hat Satellite 6.16 for RHEL 9Fixed RHSA-2026:74506
Red Hat Satellite 6.17 for RHEL 9Fixed RHSA-2026:74505
Red Hat Update Infrastructure 5Fixed RHSA-2026:67956
Not affected: 23 products
  • Migration Toolkit for Applications 8
  • Red Hat Ansible Automation Platform 2
  • Red Hat Ansible Automation Platform 2.5
  • Red Hat Ansible Automation Platform 2.6
  • Red Hat Ansible Automation Platform 2.7
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 9
  • Red Hat Hardened Images
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift AI 3.4
  • Red Hat OpenShift AI 3.5
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenShift Container Platform 5
  • Red Hat Quay 3.10
  • Red Hat Quay 3.12
  • Red Hat Quay 3.17
  • Red Hat Quay 3.18
  • Red Hat Quay 3.9
  • Red Hat Satellite 6
  • Red Hat Satellite 6.16 for RHEL 8
  • Red Hat Satellite 6.16 for RHEL 9
  • Red Hat Satellite 6.17 for RHEL 9
  • Red Hat Update Infrastructure 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-49825
  2. 2026-10-03 Alias added: GHSA-4jhm-jv67-739f
  3. 2026-10-06 Affected versions changed · Red Hat
  4. 2026-10-07 Fix available: RHSA-2026:77656 · Red Hat
  5. 2026-10-08 Fix available: Red Hat Quay 3.9 · Red Hat
  6. 2026-10-09 Fix available: RHSA-2026:79546 · Red Hat
  7. 2026-10-09 Fix available: RHSA-2026:79366 · Red Hat
  8. 2026-10-09 Fix available: Red Hat Quay 3.10, Red Hat Quay 3.12 · Red Hat
  9. 2026-10-12 Affected versions changed · Red Hat
  10. 2026-10-13 Fix available: RHSA-2026:81110 · Red Hat
  11. 2026-10-13 Fix available: Red Hat Quay 3.18 · Red Hat
  12. 2026-10-16 Affected versions changed · Red Hat
  13. 2026-10-19 Fix available: RHSA-2026:84593 · Red Hat
  14. 2026-10-19 Fix available: RHSA-2026:84592 · Red Hat
  15. 2026-10-19 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) +1 · Red Hat
  16. 2026-10-20 Fix available: RHSA-2026:84734 · Red Hat
  17. 2026-10-20 Fix available: Red Hat OpenShift AI 3.4 · Red Hat
  18. 2026-10-22 Fix available: RHSA-2026:86891 · Red Hat
  19. 2026-10-22 Fix available: RHSA-2026:87410 · Red Hat
  20. 2026-10-23 Fix available: Red Hat OpenShift AI 2.25, Red Hat OpenShift AI 3.5 · Red Hat
  21. 2026-10-26 Fix available: RHSA-2026:90326 · Red Hat
  22. 2026-10-26 Fix available: RHSA-2026:90327 · Red Hat
  23. 2026-10-26 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4), Red Hat Enterprise Linux Server (v. 7 ELS) +1 · Red Hat
  24. 2026-10-27 Fix available: Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION) · Red Hat
  25. 2026-10-29 Fix available: RHSA-2026:90336 · Red Hat
  26. 2026-10-30 Affected versions changed · Red Hat
  27. 2026-11-06 Fix available: RHSA-2026:71177 · Red Hat

References

Other 6

  • TI-2021-19624 HTML Cleaner allows crafted and SVG embedded scripts to pass through CVSS 3.1HIGH 8.2
  • TI-2026-29705 lxml: Default configuration of iterparse() and ETCompatXMLParser() allows XXE to local files CVSS 3.1HIGH 7.5
  • TI-2022-02132 NULL Pointer Dereference in lxml/lxml CVSS 3.1HIGH 7.5
  • TI-2014-02511 Incomplete blacklist vulnerability in the lxml.html.clean module in lxml before 3.3.5… CVSS 3.1MEDIUM 6.1
  • TI-2021-09882 An XSS vulnerability was discovered in python-lxml's clean module versions before 4.6.3. CVSS 3.1MEDIUM 6.1
  • TI-2020-16868 Cross-site scripting in python-lxml CVSS 3.1MEDIUM 6.1
See all 7 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences