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

> Unauthenticated access to an OAuth2 refresh endpoint allows attackers to steal access tokens for connected services, leading to unauthorized data access and account takeover.

- **Severity:** Critical 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`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Aug 2026
- **Updated:** 5 Aug 2026
- **Also known as:** GHSA-qgvm-j2hm-6m38

## What is CVE-2026-70478?

CVE-2026-70478 is a critical vulnerability in Flowiseai Flowise, published on 4 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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 WHITELIST_URLS 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 access_token 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.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2026-70478?

2 open source packages ship an affected version, including flowise. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `flowise` | npm | All versions | 3.1.3 |
| `flowise` | npm | All versions | 3.1.3 |

Products: Flowiseai Flowise.

## How do I fix CVE-2026-70478?

Upgrade flowise to 3.1.3 or later.

## Is CVE-2026-70478 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-70478 exists.

## Other vulnerabilities in Flowiseai Flowise

- [CVE-2025-71338](https://insights.sbomify.com/CVE-2025-71338/): Flowise through 2.2.7 - Arbitrary File Write to Remote Code Execution via document-store API (critical 10.0)
- [CVE-2026-40933](https://insights.sbomify.com/CVE-2026-40933/): Flowise: Authenticated RCE Via MCP Adapters (critical 10.0)
- [CVE-2025-61913](https://insights.sbomify.com/CVE-2025-61913/): Flowise is vulnerable to arbitrary file read, arbitrary file write (critical 10.0)
- [CVE-2025-59528](https://insights.sbomify.com/CVE-2025-59528/): Flowise has Remote Code Execution vulnerability (critical 10.0)
- [CVE-2026-52098](https://insights.sbomify.com/CVE-2026-52098/): Code injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-70478 and fix it if it is affected.

What it is: CVE-2026-70478 is a critical vulnerability in Flowiseai Flowise, published on 4 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-70478 exists.

Affected packages and fixed versions:
- flowise (npm): affected all versions; fixed in 3.1.3
- flowise (npm): affected all versions; fixed in 3.1.3

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-70478/ (Markdown: https://insights.sbomify.com/CVE-2026-70478/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-70478
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-70478
- OSV: https://osv.dev/vulnerability/CVE-2026-70478

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-70478/
Summaries are generated and may contain mistakes; the official description above is the record.