Flowise: Mass Assignment in DocumentStore Create Endpoint Leads to Cross-Workspace Object Takeover (IDOR)

Exploitation

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

CVSS 4.0

7.6 · CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-41277: 3.11% estimated exploitation activity in the next 30 days; percentile 87.81 (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 Mass Assignment vulnerability in the DocumentStore creation endpoint allows authenticated users to control the primary key (id) and internal state fields of DocumentStore entities. Because the service uses repository.save() with a client-supplied primary key, the POST create endpoint behaves as an implicit UPSERT operation. This enables overwriting existing DocumentStore objects. In multi-workspace or multi-tenant deployments, this can lead to cross-workspace object takeover and broken object-level authorization (IDOR), allowing an attacker to reassign or modify DocumentStore objects belonging to other workspaces. Details The DocumentStore entity defines a globally unique primary key: The create logic is implemented as: Here is no DTO allowlist or field filtering before persistence. The entire request body is mapped directly to the entity. TypeORM save() behavior: 1. If the primary key (id) exists → UPDATE 2. If not → INSERT Because id is accepted from the client, the…

Published by the source

17 Apr 2026, 21:34 UTC

Last modified by the source

5 May 2026, 16:11 UTC

Source last checked

26 Oct 2026, 12:50 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-3prp-9gf7-4rxx

2. Revision 2 · amended · 24 Oct 2026

   Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-3prp-9gf7-4rxx

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# Patch Next advisory brief: CVE-2026-41277

Advisory: Flowise: Mass Assignment in DocumentStore Create Endpoint Leads to Cross-Workspace Object Takeover (IDOR)
IDs: CVE-2026-41277, GHSA-3prp-9gf7-4rxx
Record: https://patchnext.com/advisories/cve-2026-41277 (revision 3, source checked 26 Oct 2026, 12:50 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.6)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: flowise 3.1.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm flowise: affected <= 3.0.13; fixed in 3.1.0

## Suggested inspection (read-only)
- `npm ls flowise --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 flowise.
- 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://osv.dev/vulnerability/GHSA-3prp-9gf7-4rxx (OSV record GHSA-3prp-9gf7-4rxx lists affected ranges: npm flowise >=0 <3.1.0 (fixed))
- Verified: https://github.com/advisories/GHSA-3prp-9gf7-4rxx (GitHub-reviewed advisory GHSA-3prp-9gf7-4rxx lists affected ranges: npm flowise >=0 <=3.0.13)

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