DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks
Priority MEDIUM 60CWE-501Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Security bypass, Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Partial Red Hat: 22 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-693 and CWE-79.
Summary
DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00404 34th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial DOMPurify (cure53): 3.4.6dompurify (npm): 3.4.6Red Hat: 22 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
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| cure53 | DOMPurify | before 3.4.6 | 3.4.6 | Patch available | CNA |
| — | dompurify (npm) | before 3.4.6 | 3.4.6 | Patch available | GHSA-hpcv-96wg-7vj8 |
- DOMPurify Vendorcure53 Affected before 3.4.6 Fixed in 3.4.6 Patch available CNA
- dompurify (npm) Vendor— Affected before 3.4.6 Fixed in 3.4.6 Patch available GHSA-hpcv-96wg-7vj8
Remediation
- Fix · CNA DOMPurify (cure53) Fixed in 3.4.6
- Fix · GHSA-hpcv-96wg-7vj8 dompurify (npm) Fixed in 3.4.6 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Migration Toolkit for Virtualization | Affected | No fix yet: Fix deferred |
| Multicluster Engine for Kubernetes | Affected | No fix yet: Fix deferred |
| Node HealthCheck Operator | Affected | No fix yet: Fix deferred |
| OpenShift Lightspeed | Affected | No fix yet: Fix deferred |
| OpenShift Service Mesh 3 | Affected | No fix yet: Fix deferred |
| Red Hat AMQ Broker 7 | Affected | No fix yet: Fix deferred |
| Red Hat Advanced Cluster Management for Kubernetes 2 | Affected | No fix yet: Fix deferred |
| Red Hat Advanced Cluster Security 4 | Affected | No fix yet: Fix deferred |
| Red Hat Ansible Automation Platform 2 | Affected | No fix yet: Fix deferred |
| Red Hat Build of Podman Desktop | Affected | No fix yet: Fix deferred |
| Red Hat Ceph Storage 9 | Affected | No fix yet: Fix deferred |
| Red Hat Data Grid 8 | Affected | No fix yet: Fix deferred |
| Red Hat Developer Hub 1 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift AI (RHOAI) | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Dev Spaces | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift GitOps | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Virtualization 4 | Affected | No fix yet: Fix deferred |
| Red Hat Openshift Data Foundation 4 | Affected | No fix yet: Fix deferred |
| Red Hat build of Apache Camel for Spring Boot 4 | Affected | No fix yet: Fix deferred |
| Self-service automation portal 2 | Affected | No fix yet: Fix deferred |
Not affected: 1 product
- Red Hat Hardened Images
Timeline
- 2026-10-02 Threatist record created from CVE-2026-49458
- 2026-10-03 Alias added: GHSA-hpcv-96wg-7vj8
- 2026-10-27 Affected versions changed · Red Hat
- 2026-11-06 Affected versions changed · Red Hat
References
More cure53 Dompurify vulnerabilities
- 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-2026-29849 DOMPurify: FORBID_TAGS bypassed by function-based ADD_TAGS predicate (asymmetry with FORBID_ATTR fix) CVSS 4.0MEDIUM 6.0
- 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
Sources
- CVE-2026-49458 · CVE Program
- CVE-2026-49458 · NVD
- FIRST EPSS
- GHSA-hpcv-96wg-7vj8 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-49458 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences