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CVE-2026-46442 FlowiseAI CVE debrief

CVE-2026-46442 is a critical vulnerability in Flowise, a drag & drop user interface to build customized large language model flows. Prior to version 3.1.2, the POST /api/v1/node-custom-function endpoint lacks route-level authorization, allowing any authenticated user or API key to submit arbitrary JavaScript to the Custom JS Function node. When E2B_APIKEY is not configured, Flowise executes this code inside a NodeVM sandbox, which can be escaped to reach the host process object and execute system commands via child_process. This results in authenticated remote code execution on the Flowise server host.

Vendor
FlowiseAI
Product
Flowise
CVSS
CRITICAL 9.4
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-08
Original CVE updated
2026-07-23
Advisory published
2026-06-08
Advisory updated
2026-07-23

Who should care

Users of Flowise, especially those who have not upgraded to version 3.1.2, should be aware of this critical vulnerability. Administrators of Flowise installations should prioritize upgrading to the patched version to prevent potential attacks.

Technical summary

The vulnerability exists in the POST /api/v1/node-custom-function endpoint, which allows arbitrary JavaScript submission to the Custom JS Function node without proper authorization. This can lead to authenticated remote code execution on the Flowise server host when E2B_APIKEY is not configured.

Defensive priority

High

Recommended defensive actions

  • Upgrade Flowise to version 3.1.2 or later.
  • Review and restrict access to the POST /api/v1/node-custom-function endpoint.
  • Configure E2B_APIKEY to enhance security.

Evidence notes

The vulnerability was patched in version 3.1.2. Users can refer to the release notes [ref-4] and vendor advisory [ref-5] for more information.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-46442 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-46442

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-46442 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-46442

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.