DOMPurify: IN_PLACE returns a force-removed rawtext root whose text carries attacker markup — pure HTML reparse executes

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

not scored

EPSS

• CVE-2026-109345: 0.25% estimated exploitation activity in the next 30 days; percentile 16.41 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Environment - dompurify 3.4.15 (current npm release); reproduced independently on jsdom 30.0.1 and 29.1.1 (Node.js 20.x / 26.x) - Config: DOMPurify.sanitize(node, { INPLACE: true }) on a Node input; SAFEFORXML at its default (true) Summary The 3.4.9 fix for the INPLACE detached-root class added two protections on the INPLACE return path: a fail-closed TypeError in forceRemove when a node selected for removal cannot be detached, and a neutralizeSubtree pass (dist/purify.js line 1336) that strips non-allowlisted attributes from removed subtrees. Both miss the rawtext text-content form. When the force-removed root is a rawtext element (<style), the payload lives in the node's text: the node detaches fine (the TypeError guard is not reached), neutralizeSubtree strips nothing (there are no attributes), and the INPLACE exit returns the detached, never-sanitized <style whose text still carries live markup. Serializing that node and re-parsing it in plain HTML context materializes the…

Published by the source

5 Oct 2026, 23:43 UTC

Last modified by the source

13 Oct 2026, 02:56 UTC

Source last checked

26 Oct 2026, 13:06 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-6688-9rhm-gjv2

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-6688-9rhm-gjv2

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-6688-9rhm-gjv2

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# Patch Next advisory brief: CVE-2026-109345

Advisory: DOMPurify: IN_PLACE returns a force-removed rawtext root whose text carries attacker markup — pure HTML reparse executes
IDs: CVE-2026-109345, GHSA-6688-9rhm-gjv2
Record: https://patchnext.com/advisories/ghsa-6688-9rhm-gjv2 (revision 3, source checked 26 Oct 2026, 13:06 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Unrated
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: dompurify 3.4.16. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm dompurify: affected <= 3.4.15; fixed in 3.4.16

## Suggested inspection (read-only)
- `npm ls dompurify --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on dompurify.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-6688-9rhm-gjv2 (GitHub-reviewed advisory GHSA-6688-9rhm-gjv2 lists affected ranges: npm dompurify >=0 <=3.4.15)
- Verified: https://osv.dev/vulnerability/GHSA-6688-9rhm-gjv2 (OSV record GHSA-6688-9rhm-gjv2 lists affected ranges: npm dompurify >=0 <3.4.16 (fixed))

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