# CVE-2026-86075: n8n: Unauthenticated Persistent Storage Exhaustion via OAuth Dynamic Client Registration Endpoint

> Unauthenticated attackers can exhaust database storage by sending oversized values to the OAuth Dynamic Client Registration endpoint in n8n.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/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:** 8 Sep 2026
- **Updated:** 9 Sep 2026
- **Also known as:** GHSA-hh89-3r9w-qj3j, MINI-8hg7-cqv7-353c, ROOT-APP-NPM-CVE-2026-86075

## What is CVE-2026-86075?

CVE-2026-86075 is a high-severity denial of service vulnerability in N8n N8n, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

n8n is an open source workflow automation platform. Prior to 2.37.7 and 2.38.2, the OAuth Dynamic Client Registration endpoint bounded redirect_uris but accepted arbitrarily large client_name and grant_types values. An unauthenticated remote caller could repeatedly persist oversized values in oauth_clients and exhaust database storage. The affected validation is in packages/cli/src/modules/oauth-server/oauth-server.service.ts, including MAX_CLIENT_NAME_LENGTH and MAX_GRANT_TYPES. This issue is fixed in versions 2.37.7 and 2.38.2.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling)

## Which versions are affected by CVE-2026-86075?

4 open source packages ship an affected version, including n8n. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `n8n` | npm | All versions | 2.37.7 |
| `n8n` | npm | All versions | 2.37.7 |
| `n8n` | npm | From 2.38.0 | 2.38.2 |
| `n8n` | npm | From 2.38.0 | 2.38.2 |

Products: N8n N8n.

## How do I fix CVE-2026-86075?

Upgrade n8n to a fixed version for your release line: 2.37.7 or 2.38.2.

## Is CVE-2026-86075 being exploited?

There is no known exploitation of CVE-2026-86075 in the wild and no public exploit code.

## Other vulnerabilities in N8n N8n

- [CVE-2025-68613](https://insights.sbomify.com/CVE-2025-68613/): n8n Improper Control of Dynamically-Managed Code Resources (critical 10.0, exploited in the wild)
- [CVE-2026-21877](https://insights.sbomify.com/CVE-2026-21877/): n8n is vulnerable to Remote Code Execution via Arbitrary File Write (critical 10.0)
- [CVE-2026-21858](https://insights.sbomify.com/CVE-2026-21858/): n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling (critical 10.0)
- [CVE-2026-1470](https://insights.sbomify.com/CVE-2026-1470/): n8n Unsafe Workflow Expression Evaluation Allows Remote Code Execution (critical 9.9)
- [CVE-2025-68668](https://insights.sbomify.com/CVE-2025-68668/): n8n Vulnerable to Arbitrary Command Execution in Pyodide based Python Code Node (critical 9.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-86075 and fix it if it is affected.

What it is: CVE-2026-86075 is a high-severity denial of service vulnerability in N8n N8n, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-86075 in the wild and no public exploit code.

Affected packages and fixed versions:
- n8n (npm): affected all versions; fixed in 2.37.7
- n8n (npm): affected all versions; fixed in 2.37.7
- n8n (npm): affected from 2.38.0; fixed in 2.38.2
- n8n (npm): affected from 2.38.0; fixed in 2.38.2

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-2026-86075/ (Markdown: https://insights.sbomify.com/CVE-2026-86075/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-86075
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-86075
- OSV: https://osv.dev/vulnerability/CVE-2026-86075

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-86075/
Summaries are generated and may contain mistakes; the official description above is the record.