DOMPurify before 3.4.12 Hook Bypass via CUSTOM_ELEMENT_HANDLING
cure53 · DOMPurify
5.1MediumCVSS 4.0
Recommended action
Within 7 days
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available
Distribution package intelligence
Ubuntu vendor package status
Canonical’s release and source-package findings are shown separately from local repository availability.
1 package state
Repository candidate not checked
A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.
Ubuntu release
Source package
Vendor state
Fixed version
Evidence
Ubuntu 24.04 LTSnoble · standard archive
node-dompurify
Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
1 current
CVE-2026-66010 · CSAF 2.0 · revision 3 · finalRed Hat Product Securitydompurify: DOMPurify: Cross-Site Scripting (XSS) via custom element attribute bypass
93 known affected
The vendor explicitly identifies these products as affected by this CVE.
cryostat-openshift-console-plugin-npm as a component of Cryostat 4
dompurify as a component of Cryostat 4
grafana-infinity-datasource-npm as a component of Cryostat 4
migration-toolkit-virtualization/mtv-console-plugin-rhel9 as a component of Migration Toolkit for Virtualization
multicluster-engine/console-mce-rhel9 as a component of Multicluster Engine for Kubernetes
workload-availability/node-healthcheck-must-gather-rhel9 as a component of Node HealthCheck Operator
workload-availability/node-healthcheck-operator-bundle as a component of Node HealthCheck Operator
workload-availability/node-healthcheck-rhel9-operator as a component of Node HealthCheck Operator
openshift-lightspeed/lightspeed-agentic-console-rhel9 as a component of OpenShift Lightspeed
openshift-lightspeed/lightspeed-console-plugin-419-rhel9 as a component of OpenShift Lightspeed
openshift-lightspeed/lightspeed-console-plugin-pf5-rhel9 as a component of OpenShift Lightspeed
openshift-lightspeed/lightspeed-console-plugin-rhel9 as a component of OpenShift Lightspeed
Summary
A flaw was found in DOMPurify. This vulnerability allows attackers to bypass application security policies by preserving sensitive attributes on custom elements. These attributes can then be re-injected into web page content, leading to Cross-Site Scripting (XSS) attacks. An attacker could exploit this to execute malicious scripts in a user's browser, potentially leading to information disclosure or unauthorized actions.
Remediation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Optional official sources
National CERT insights ?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.
Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.
Official European source
ENISA European Vulnerability Database
Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.
1 current
ENISA EUVD identifier
EUVD-2026-48582
No EUVD known-exploited evidence
ENISA has published the identifier mapping but no EUVD description has been stored yet.
EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days
Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.
Patch available
01
What, why and how
DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into innerHTML sinks, creating second-order XSS gadgets.
What
DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into innerHTML sinks, creating second-order XSS gadgets.
Why
Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.
How
An attacker operating through a network path may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
DOMPurify before 3.4.12 fails to execute afterSanitizeElements hook for custom elements allowed via CUSTOM_ELEMENT_HANDLING.tagNameCheck, allowing attributes to bypass application security policies. Attackers can preserve sensitive attributes on custom elements that later re-inject them into innerHTML sinks, creating second-order XSS gadgets.
Why
Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.
How
An attacker operating through a network path may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation ?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No confirmed evidence
No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material ?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.Reference recorded
A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
Likely attack path
a network path → Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
Active interaction required
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Not a CVSS 4.0 base metric
Weakness ?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'). The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
CVSS vector ?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
Common Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.ATNoneAttack requirements: No additional deployment or execution condition is required.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIActiveUser interaction: A user must take a deliberate action for exploitation to succeed.VCNoneVulnerable-system confidentiality: No direct loss is represented by this metric.VINoneVulnerable-system integrity: No direct loss is represented by this metric.VANoneVulnerable-system availability: No direct loss is represented by this metric.SCLowSubsequent-system confidentiality: A successful attack can cause a limited loss.SILowSubsequent-system integrity: A successful attack can cause a limited loss.SANoneSubsequent-system availability: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
Only matched European and national findings are included. Language selectors and unavailable sources are omitted.
ENISA EUVD · EUVD-2026-48582Official EUVD mapping
0 linked advisory records.
Official EUVD recordBSI · German · WID-SEC-W-2026-3098IBM DataPower Gateway: Mehrere Schwachstellen
Ein Angreifer kann mehrere Schwachstellen in IBM DataPower Gateway ausnutzen, um Sicherheitsvorkehrungen zu umgehen oder einen Cross Site Scripting Angriff durchzuführen.
Official advisoryCERT-FR · French · CERTFR-2026-AVI-1067Multiples vulnérabilités dans les produits IBM
Operational remediation based on structured source evidence.
Status ?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
cryostat-openshift-console-plugin-npm as a component of Cryostat 4; dompurify as a component of Cryostat 4; grafana-infinity-datasource-npm as a component of Cryostat 4; migration-toolkit-virtualization/mtv-console-plugin-rhel9 as a component of Migration Toolkit for Virtualization; multicluster-engine/console-mce-rhel9 as a component of Multicluster Engine for Kubernetes; workload-availability/node-healthcheck-must-gather-rhel9 as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-operator-bundle as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-rhel9-operator as a component of Node HealthCheck Operator; openshift-lightspeed/lightspeed-agentic-console-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-419-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-pf5-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-rhel9 as a component of OpenShift Lightspeed; openshift-service-mesh/kiali-ossmc-rhel9 as a component of OpenShift Service Mesh 3; openshift-service-mesh/kiali-rhel9 as a component of OpenShift Service Mesh 3; 3scale-amp2/system-rhel7 as a component of Red Hat 3scale API Management Platform 2; 3scale-amp2/system-rhel8 as a component of Red Hat 3scale API Management Platform 2; 3scale-amp2/system-rhel9 as a component of Red Hat 3scale API Management Platform 2; 3scale-amp21/system as a component of Red Hat 3scale API Management Platform 2; 3scale-amp22/system as a component of Red Hat 3scale API Management Platform 2; rhacm2/console-rhel9 as a component of Red Hat Advanced Cluster Management for Kubernetes 2; advanced-cluster-security/rhacs-main-rhel8 as a component of Red Hat Advanced Cluster Security 4; advanced-cluster-security/rhacs-main-rhel9 as a component of Red Hat Advanced Cluster Security 4; dompurify as a component of Red Hat AMQ Broker 7; ansible-automation-platform-26/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; ansible-automation-platform-27/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; automation-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-eda-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-gateway.src as a component of Red Hat Ansible Automation Platform 2; automation-platform-ui.src as a component of Red Hat Ansible Automation Platform 2; dompurify as a component of Red Hat build of Apache Camel - HawtIO 4; and 63 more
Fixed
3.4.12
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
04
Evidence and provenance
Published 24 Jul 2026 · Last source change 24 Jul 2026, 14:14 UTC · CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source ?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-48582
Product sourceVendor CSAF · Red Hat Product Security
Remediation sourceVendor CSAF · Red Hat Product Security
CWE sourceCNA
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Affected versionsThe structured affected or fixed version information changed.
Before
migration-toolkit-virtualization/mtv-console-plugin-rhel9 as a component of Migration Toolkit for Virtualization; multicluster-engine/console-mce-rhel9 as a component of Multicluster Engine for Kubernetes; workload-availability/node-healthcheck-must-gather-rhel9 as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-operator-bundle as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-rhel9-operator as a component of Node HealthCheck Operator; openshift-lightspeed/lightspeed-agentic-console-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-419-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-pf5-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-rhel9 as a component of OpenShift Lightspeed; openshift-service-mesh/kiali-ossmc-rhel9 as a component of OpenShift Service Mesh 3; openshift-service-mesh/kiali-rhel9 as a component of OpenShift Service Mesh 3; rhacm2/console-rhel9 as a component of Red Hat Advanced Cluster Management for Kubernetes 2; advanced-cluster-security/rhacs-main-rhel8 as a component of Red Hat Advanced Cluster Security 4; advanced-cluster-security/rhacs-main-rhel9 as a component of Red Hat Advanced Cluster Security 4; ansible-automation-platform-26/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; ansible-automation-platform-27/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; automation-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-eda-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-gateway.src as a component of Red Hat Ansible Automation Platform 2; automation-platform-ui.src as a component of Red Hat Ansible Automation Platform 2; cockpit-image-builder as a component of Red Hat Enterprise Linux 10; cockpit-image-builder.src as a component of Red Hat Enterprise Linux 10; grafana as a component of Red Hat Enterprise Linux 10; grafana-pcp as a component of Red Hat Enterprise Linux 10; grafana-pcp.src as a component of Red Hat Enterprise Linux 10; grafana-selinux as a component of Red Hat Enterprise Linux 10; grafana.src as a component of Red Hat Enterprise Linux 10; librados-devel as a component of Red Hat Enterprise Linux 10; librados2 as a component of Red Hat Enterprise Linux 10; libradospp-devel as a component of Red Hat Enterprise Linux 10; and 37 more
After
cryostat-openshift-console-plugin-npm as a component of Cryostat 4; dompurify as a component of Cryostat 4; grafana-infinity-datasource-npm as a component of Cryostat 4; migration-toolkit-virtualization/mtv-console-plugin-rhel9 as a component of Migration Toolkit for Virtualization; multicluster-engine/console-mce-rhel9 as a component of Multicluster Engine for Kubernetes; workload-availability/node-healthcheck-must-gather-rhel9 as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-operator-bundle as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-rhel9-operator as a component of Node HealthCheck Operator; openshift-lightspeed/lightspeed-agentic-console-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-419-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-pf5-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-rhel9 as a component of OpenShift Lightspeed; openshift-service-mesh/kiali-ossmc-rhel9 as a component of OpenShift Service Mesh 3; openshift-service-mesh/kiali-rhel9 as a component of OpenShift Service Mesh 3; 3scale-amp2/system-rhel7 as a component of Red Hat 3scale API Management Platform 2; 3scale-amp2/system-rhel8 as a component of Red Hat 3scale API Management Platform 2; 3scale-amp2/system-rhel9 as a component of Red Hat 3scale API Management Platform 2; 3scale-amp21/system as a component of Red Hat 3scale API Management Platform 2; 3scale-amp22/system as a component of Red Hat 3scale API Management Platform 2; rhacm2/console-rhel9 as a component of Red Hat Advanced Cluster Management for Kubernetes 2; advanced-cluster-security/rhacs-main-rhel8 as a component of Red Hat Advanced Cluster Security 4; advanced-cluster-security/rhacs-main-rhel9 as a component of Red Hat Advanced Cluster Security 4; dompurify as a component of Red Hat AMQ Broker 7; ansible-automation-platform-26/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; ansible-automation-platform-27/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; automation-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-eda-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-gateway.src as a component of Red Hat Ansible Automation Platform 2; automation-platform-ui.src as a component of Red Hat Ansible Automation Platform 2; dompurify as a component of Red Hat build of Apache Camel - HawtIO 4; and 63 more
Affected versionsThe structured affected or fixed version information changed.
Before
migration-toolkit-virtualization/mtv-console-plugin-rhel9 as a component of Migration Toolkit for Virtualization; multicluster-engine/console-mce-rhel9 as a component of Multicluster Engine for Kubernetes; workload-availability/node-healthcheck-must-gather-rhel9 as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-operator-bundle as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-rhel9-operator as a component of Node HealthCheck Operator; openshift-lightspeed/lightspeed-agentic-console-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-419-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-pf5-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-rhel9 as a component of OpenShift Lightspeed; openshift-service-mesh/kiali-ossmc-rhel9 as a component of OpenShift Service Mesh 3; openshift-service-mesh/kiali-rhel9 as a component of OpenShift Service Mesh 3; rhacm2/console-rhel9 as a component of Red Hat Advanced Cluster Management for Kubernetes 2; advanced-cluster-security/rhacs-main-rhel8 as a component of Red Hat Advanced Cluster Security 4; advanced-cluster-security/rhacs-main-rhel9 as a component of Red Hat Advanced Cluster Security 4; ansible-automation-platform-26/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; ansible-automation-platform-27/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; automation-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-eda-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-gateway.src as a component of Red Hat Ansible Automation Platform 2; automation-platform-ui.src as a component of Red Hat Ansible Automation Platform 2; cockpit-image-builder as a component of Red Hat Enterprise Linux 10; cockpit-image-builder.src as a component of Red Hat Enterprise Linux 10; grafana as a component of Red Hat Enterprise Linux 10; grafana-pcp as a component of Red Hat Enterprise Linux 10; grafana-pcp.src as a component of Red Hat Enterprise Linux 10; grafana-selinux as a component of Red Hat Enterprise Linux 10; grafana.src as a component of Red Hat Enterprise Linux 10; librados-devel as a component of Red Hat Enterprise Linux 10; librados2 as a component of Red Hat Enterprise Linux 10; libradospp-devel as a component of Red Hat Enterprise Linux 10; and 36 more
After
migration-toolkit-virtualization/mtv-console-plugin-rhel9 as a component of Migration Toolkit for Virtualization; multicluster-engine/console-mce-rhel9 as a component of Multicluster Engine for Kubernetes; workload-availability/node-healthcheck-must-gather-rhel9 as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-operator-bundle as a component of Node HealthCheck Operator; workload-availability/node-healthcheck-rhel9-operator as a component of Node HealthCheck Operator; openshift-lightspeed/lightspeed-agentic-console-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-419-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-pf5-rhel9 as a component of OpenShift Lightspeed; openshift-lightspeed/lightspeed-console-plugin-rhel9 as a component of OpenShift Lightspeed; openshift-service-mesh/kiali-ossmc-rhel9 as a component of OpenShift Service Mesh 3; openshift-service-mesh/kiali-rhel9 as a component of OpenShift Service Mesh 3; rhacm2/console-rhel9 as a component of Red Hat Advanced Cluster Management for Kubernetes 2; advanced-cluster-security/rhacs-main-rhel8 as a component of Red Hat Advanced Cluster Security 4; advanced-cluster-security/rhacs-main-rhel9 as a component of Red Hat Advanced Cluster Security 4; ansible-automation-platform-26/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; ansible-automation-platform-27/gateway-rhel9 as a component of Red Hat Ansible Automation Platform 2; automation-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-eda-controller.src as a component of Red Hat Ansible Automation Platform 2; automation-gateway.src as a component of Red Hat Ansible Automation Platform 2; automation-platform-ui.src as a component of Red Hat Ansible Automation Platform 2; cockpit-image-builder as a component of Red Hat Enterprise Linux 10; cockpit-image-builder.src as a component of Red Hat Enterprise Linux 10; grafana as a component of Red Hat Enterprise Linux 10; grafana-pcp as a component of Red Hat Enterprise Linux 10; grafana-pcp.src as a component of Red Hat Enterprise Linux 10; grafana-selinux as a component of Red Hat Enterprise Linux 10; grafana.src as a component of Red Hat Enterprise Linux 10; librados-devel as a component of Red Hat Enterprise Linux 10; librados2 as a component of Red Hat Enterprise Linux 10; libradospp-devel as a component of Red Hat Enterprise Linux 10; and 37 more
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
CVE-2026-66010: DOMPurify before 3.4.12 Hook Bypass via CUSTOM_ELEMENT_HANDLING | BlackTree
