Description
DOMPurify through 3.3.3 fails to sanitize DOM elements passed via IN_PLACE mode when the element originates from a different window/realm (e.g., an iframe's contentDocument). A cross-realm instanceof check in the private _isNode() function returns false for foreign-realm nodes, causing DOMPurify to stringify the element (yielding '[object HTMLDivElement]'), silently reset IN_PLACE to false, and return the unsanitized element unchanged with any XSS payloads intact.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| cure53 | DOMPurify | ≤ 3.3.3 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | node-dompurify | 3.4.5+dfsg-1 | — |
| Debian 13 | node-dompurify | No fix yet | — |
| Debian 12 | node-dompurify | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | node-dompurify | No fix yet | — |
| Ubuntu 24.04 LTS | node-dompurify | No fix yet | — |
| Ubuntu 22.04 LTS | node-dompurify | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | grafana13.1 | 13.1.3-0.1.1.hum1 | RHSA-2026:54517 |
Advisories 1
- RHSA-2026:54517 Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update Red Hat Security Advisories (RHSA) · Oct 20, 2026
References
- GitHub Security Advisory (GHSA-4w3q-35jp-p934) vendor-advisory
- VulnCheck Advisory: DOMPurify before 3.4.4 Cross-Site Scripting via IN_PLACE mode third-party-advisory