ApostropheCMS: Unauthenticated resource exhaustion via pre-auth aposBigUpload processing in @apostrophecms/import-export

Exploitation

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

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2026-113711: 0.56% estimated exploitation activity in the next 30 days; percentile 46.71 (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.

Summary A potential unauthenticated denial-of-service vulnerability exists in the chunked import upload path used by @apostrophecms/import-export. The affected import API routes invoke: self.apos.http.bigUploadMiddleware() before the actual import handler performs its authentication check. Because no authorize callback is supplied to bigUploadMiddleware(), unauthenticated requests can reach the aposBigUpload start, chunk, and end operations before the later req.user check rejects the import. As a result, an unauthenticated remote attacker can create server-side upload state, write chunk data to upload storage, trigger temporary-file processing, and cause attacker-controlled cleanup operations before authentication is enforced. Affected Component Package: @apostrophecms/import-export Confirmed affected version: 3.6.2 Potential earlier affected versions: The issue may affect earlier 3.x releases in which the current big-upload-based import implementation is present. I have not yet…

Published by the source

21 Oct 2026, 13:51 UTC

Last modified by the source

21 Oct 2026, 14:00 UTC

Source last checked

26 Oct 2026, 13:07 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-86wm-68pq-5jwq

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-86wm-68pq-5jwq

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-86wm-68pq-5jwq

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# Patch Next advisory brief: CVE-2026-113711

Advisory: ApostropheCMS: Unauthenticated resource exhaustion via pre-auth aposBigUpload processing in @apostrophecms/import-export
IDs: CVE-2026-113711, GHSA-86wm-68pq-5jwq
Record: https://patchnext.com/advisories/cve-2026-113711 (revision 3, source checked 26 Oct 2026, 13:07 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @apostrophecms/import-export 3.7.0; apostrophe 4.33.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @apostrophecms/import-export: affected < 3.7.0; fixed in 3.7.0
- npm apostrophe: affected < 4.33.0; fixed in 4.33.0

## Suggested inspection (read-only)
- `npm ls @apostrophecms/import-export --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.
- `npm ls apostrophe --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 @apostrophecms/import-export, apostrophe.
- 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-86wm-68pq-5jwq (GitHub-reviewed advisory GHSA-86wm-68pq-5jwq lists affected ranges: npm apostrophe >=0 =0 <3.7.0)
- Verified: https://osv.dev/vulnerability/GHSA-86wm-68pq-5jwq (OSV record GHSA-86wm-68pq-5jwq lists affected ranges: npm apostrophe >=0 =0 <3.7.0 (fixed))

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