---
title: "CVE-2026-70478: Flowise: Unauthenticated OAuth2 token refresh endpoint returns access tokens — enables token theft for any connected service"
url: https://erroneo.us/security/cve/CVE-2026-70478/
description: "CVE-2026-70478 (flowise (npm)): Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.3, the POST…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-08-04
date_modified: 2026-08-05
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-70478"
kev: false
cvss: 9.2
epss: 0.00615
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-70478: Flowise: Unauthenticated OAuth2 token refresh endpoint returns access tokens — enables token theft for any connected service

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.6% , percentile 49: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 49% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes flowise (npm) <= 3.1.2, fixed in 3.1.3 . Check your lockfile, including transitive dependencies.

## What it is

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to 3.1.3, the POST /api/v1/oauth2-credential/refresh/:credentialId endpoint is included in WHITELISTURLS and requires no authentication. The endpoint decrypts the stored credential, sends a refresh request to the configured OAuth provider with the client secret and refresh token, and returns the refreshed accesstoken in the response body. An attacker with a credential ID can use the token to access the victim's connected service and can also exhaust refresh-token quota. This issue is fixed in 3.1.3.

## Affected packages

- npm `flowise` <= 3.1.2 → fixed: 3.1.3

## Affected products (CVE record)

- FlowiseAI Flowise: < 3.1.2

## Severity

- GitHub_M CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N`
- GitHub CVSS 4.0: 9.2 `CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.61% probability of exploitation activity in the next 30 days; percentile 49.

## Sources

- [GitHub Advisory GHSA-qgvm-j2hm-6m38](https://github.com/advisories/GHSA-qgvm-j2hm-6m38)
- [CVE.org record CVE-2026-70478](https://www.cve.org/CVERecord?id=CVE-2026-70478)
- [NVD entry CVE-2026-70478](https://nvd.nist.gov/vuln/detail/CVE-2026-70478)
- [github.com](https://github.com/FlowiseAI/Flowise/security/advisories/GHSA-qgvm-j2hm-6m38)

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Source page: https://erroneo.us/security/cve/CVE-2026-70478/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt