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TI-2026-29849 Aliases CVE-2026-41240GHSA-h7mw-gpvr-xq4m

DOMPurify: FORBID_TAGS bypassed by function-based ADD_TAGS predicate (asymmetry with FORBID_ATTR fix)

Priority MEDIUM 60CWE-183Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
Present
Impact type
Cross-site scripting
Confidentiality · integrity · availability
None · High · None
Fix status
Partial Red Hat: 18 fixed, 10 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-79.

Summary

DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Versions prior to 3.4.0 have an inconsistency between FORBID_TAGS and FORBID_ATTR handling when function-based ADD_TAGS is used. Commit c361baa added an early exit for FORBID_ATTR at line 1214. The same fix was not applied to FORBID_TAGS. At line 1118-1123, when EXTRA_ELEMENT_HANDLING.tagCheck returns true, the short-circuit evaluation skips the FORBID_TAGS check entirely. This allows forbidden elements to survive sanitization with their attributes intact. Version 3.4.0 patches the issue.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00313 24th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial DOMPurify (cure53): 3.4.0dompurify (npm): 3.4.0Red Hat: 18 advisoriesRed Hat: 18 fixed, 10 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
cure53DOMPurifybefore 3.4.03.4.0Patch availableCNA
—dompurify (npm)before 3.4.03.4.0Patch availableGHSA-h7mw-gpvr-xq4m
  • DOMPurify Vendorcure53 Affected before 3.4.0 Fixed in 3.4.0 Patch available CNA
  • dompurify (npm) Vendor— Affected before 3.4.0 Fixed in 3.4.0 Patch available GHSA-h7mw-gpvr-xq4m

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:cure53:dompurify:*:*:*:*:*:*:*:*before 3.4.0Vulnerablecure53
  • cpe:2.3:a:cure53:dompurify:*:*:*:*:*:*:*:* Versions before 3.4.0 Vulnerable ·cure53

Remediation

  • Fix · CNA DOMPurify (cure53) Fixed in 3.4.0
  • Fix · GHSA-h7mw-gpvr-xq4m dompurify (npm) Fixed in 3.4.0 Advisory →

Red Hat 18 advisories

  • RHSA-2026:86618 Released 2026-10-21 · Red Hat rating Critical
    New container image: rhceph-9.2
    • Red Hat Ceph Storage 9.2 registry.redhat.io/rhceph/rhceph-9-rhel10
  • RHSA-2026:59360 Released 2026-08-25 · Red Hat rating Important
    Apicurio Registry (container images) release and security update [ 3.3.1 GA ]
    • Red Hat build of Apicurio Registry 3.3.1
  • RHSA-2026:36108 Released 2026-07-07 · Red Hat rating Important
    OpenShift Virtualization v4.13 Images
    • Red Hat Container Native Virtualization 4.13 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
Show 15 more Red Hat advisories
  • RHSA-2026:36107 Released 2026-07-07 · Red Hat rating Important
    OpenShift Virtualization v4.15 Images
    • Red Hat Container Native Virtualization 4.15 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
  • RHSA-2026:34608 Released 2026-07-02 · Red Hat rating Important
    Streams for Apache Kafka 2.9.4 release and security update
    • Streams for Apache Kafka 2.9.4
  • RHSA-2026:34160 Released 2026-07-01 · Red Hat rating Important
    Red Hat Ansible Automation Platform 2.6 Product Security and Bug Fix Update
    • Red Hat Ansible Automation Platform 2.6 for RHEL 9 automation-controller-4.7.13-2.el9ap, automation-controller-cli-4.7.13-2.el9ap, automation-controller-server-4.7.13-2.el9ap +7
  • RHSA-2026:28010 Released 2026-06-22 · Red Hat rating Important
    Red Hat build of Cryostat security update
    • Cryostat 4 on RHEL 9 cryostat/cryostat-openshift-console-plugin-rhel9, cryostat/cryostat-reports-rhel9, cryostat/cryostat-rhel9 +3
  • RHSA-2026:28001 Released 2026-06-22 · Red Hat rating Moderate
    OpenShift Virtualization v4.17 Images
    • Red Hat Container Native Virtualization 4.17 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
  • RHSA-2026:27967 Released 2026-06-22 · Red Hat rating Moderate
    OpenShift Virtualization v4.20 Images
    • Red Hat Container Native Virtualization 4.20 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
  • RHSA-2026:27944 Released 2026-06-22 · Red Hat rating Important
    OpenShift Virtualization v4.14 Images
    • Red Hat Container Native Virtualization 4.14 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
  • RHSA-2026:27879 Released 2026-06-22 · Red Hat rating Moderate
    OpenShift Virtualization v4.21 Images
    • Red Hat Container Native Virtualization 4.21 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
  • RHSA-2026:27875 Released 2026-06-22 · Red Hat rating Moderate
    OpenShift Virtualization v4.18 Images
    • Red Hat Container Native Virtualization 4.18 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
  • RHSA-2026:27872 Released 2026-06-22 · Red Hat rating Moderate
    OpenShift Virtualization v4.19 Images
    • Red Hat Container Native Virtualization 4.19 registry.redhat.io/container-native-virtualization/kubevirt-console-plugin-rhel9
  • RHSA-2026:24977 Released 2026-06-10 · Red Hat rating Important
    RHOAI 2.25.7 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 2.25 registry.redhat.io/rhoai/odh-caikit-nlp-rhel9, registry.redhat.io/rhoai/odh-caikit-tgis-serving-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9 +34
  • RHSA-2026:22619 Released 2026-06-02 · Red Hat rating Important
    Red Hat Data Grid 8.6.1 security update
    • Red Hat Data Grid 8.6.1
  • RHSA-2026:21772 Released 2026-05-28 · Red Hat rating Important
    Red Hat OpenShift Dev Spaces 3.28.0 Release.
    • Red Hat OpenShift Dev Spaces 3.28 registry.redhat.io/devspaces/code-rhel9, registry.redhat.io/devspaces/dashboard-rhel9, registry.redhat.io/devspaces/openvsx-rhel9 +3
  • RHSA-2026:21338 Released 2026-05-27 · Red Hat rating Important
    Red Hat Developer Hub 1.8.7 release.
    • Red Hat Developer Hub 1.8 registry.redhat.io/rhdh/rhdh-hub-rhel9, registry.redhat.io/rhdh/rhdh-rhel9-operator
  • RHSA-2026:16476 Released 2026-05-12 · Red Hat rating Important
    Kiali 1.73.30 for Red Hat OpenShift Service Mesh 2.6
    • Red Hat OpenShift Service Mesh 2.6 registry.redhat.io/openshift-service-mesh/kiali-ossmc-rhel8, registry.redhat.io/openshift-service-mesh/kiali-rhel8

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Cryostat 4AffectedNo fix yet
Migration Toolkit for VirtualizationAffectedNo fix planned: Will not fix
Red Hat 3scale API Management Platform 2AffectedNo fix planned: Will not fix
Red Hat Ceph Storage 9AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)AffectedNo fix yet
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift GitOpsAffectedNo fix yet
Red Hat Openshift Data Foundation 4AffectedNo fix yet
Red Hat build of Apicurio Registry 2AffectedNo fix planned: Will not fix
Self-service automation portal 2AffectedNo fix yet
Cryostat 4 on RHEL 9Fixed RHSA-2026:28010
Red Hat Ansible Automation Platform 2.6 for RHEL 9Fixed RHSA-2026:34160
Red Hat Ceph Storage 9.2Fixed RHSA-2026:86618
Red Hat Container Native Virtualization 4.13Fixed RHSA-2026:36108
Red Hat Container Native Virtualization 4.14Fixed RHSA-2026:27944
Red Hat Container Native Virtualization 4.15Fixed RHSA-2026:36107
Red Hat Container Native Virtualization 4.17Fixed RHSA-2026:28001
Red Hat Container Native Virtualization 4.18Fixed RHSA-2026:27875
Red Hat Container Native Virtualization 4.19Fixed RHSA-2026:27872
Red Hat Container Native Virtualization 4.20Fixed RHSA-2026:27967
Red Hat Container Native Virtualization 4.21Fixed RHSA-2026:27879
Red Hat Data Grid 8.6.1Fixed RHSA-2026:22619
Red Hat Developer Hub 1.8Fixed RHSA-2026:21338
Red Hat OpenShift AI 2.25Fixed RHSA-2026:24977
Red Hat OpenShift Dev Spaces 3.28Fixed RHSA-2026:21772
Red Hat OpenShift Service Mesh 2.6Fixed RHSA-2026:16476
Red Hat build of Apicurio Registry 3.3.1Fixed RHSA-2026:59360
Streams for Apache Kafka 2.9.4Fixed RHSA-2026:34608
Not affected: 26 products
  • Cryostat 4 on RHEL 9
  • Migration Toolkit for Virtualization
  • Multicluster Engine for Kubernetes
  • Node HealthCheck Operator
  • OpenShift Lightspeed
  • OpenShift Service Mesh 3
  • Red Hat 3scale API Management Platform 2
  • Red Hat Advanced Cluster Security 4
  • Red Hat Ansible Automation Platform 2
  • Red Hat Ansible Automation Platform 2.6 for RHEL 9
  • Red Hat Build of Podman Desktop
  • Red Hat Ceph Storage 9.2
  • Red Hat Developer Hub 1.8
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat Hardened Images
  • Red Hat OpenShift AI (RHOAI)
  • Red Hat OpenShift AI 2.25
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenShift Dev Spaces 3.28
  • Red Hat OpenShift Service Mesh 2.6
  • Red Hat OpenShift Virtualization 4
  • Red Hat Process Automation 7
  • Red Hat build of Apache Camel - HawtIO 4
  • streams for Apache Kafka 3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-41240
  2. 2026-10-03 Alias added: GHSA-h7mw-gpvr-xq4m
  3. 2026-10-09 Fix available: RHSA-2026:59360 · Red Hat
  4. 2026-10-09 Fix available: Red Hat build of Apicurio Registry 3.3.1 · Red Hat
  5. 2026-10-21 Fix available: RHSA-2026:86618 · Red Hat
  6. 2026-10-21 Fix available: Red Hat Ceph Storage 9.2 · Red Hat
  7. 2026-11-06 Fix available: RHSA-2026:27944 · Red Hat

References

Exploit 1

Patch 1

Advisory 1

Other 2

  • TI-2026-34986 DOMPurify XSS via `selectedcontent` re-clone CVSS 3.1HIGH 8.2
  • TI-2026-36811 DOMPurify IN_PLACE Sanitization Bypass via Attached Shadow Root Inside <template>.content CVSS 4.0MEDIUM 6.3
  • TI-2026-36614 DOMPurify: IN_PLACE mode preserves attributes of a clobbered root element, allowing XSS via attacker-controlled root DOM CVSS 3.1MEDIUM 6.1
  • TI-2026-36613 DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks CVSS 3.1MEDIUM 6.1
  • TI-2025-19705 Cross-site scripting in cure53 DOMPurify CVSS 3.1MEDIUM 6.1
  • TI-2026-46952 DOMPurify before 3.3.2 Mutation XSS via Re-Contextualization CVSS 4.0MEDIUM 5.3
See all 25 →

Sources

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