High severity · published Sep 8, 2026
CVE-2026-86075
n8n: Unauthenticated Persistent Storage Exhaustion via OAuth Dynamic Client Registration Endpoint
7.5
CVSS
0.6%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 49% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
N8
n8n · n8n-io
< 2.37.7; >= 2.38.0, < 2.38.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-86075
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-86075
Release Notes
https://github.com/n8n-io/n8n/releases/tag/n8n@2.37.7
Release Notes
https://github.com/n8n-io/n8n/releases/tag/n8n@2.38.2
Mitigation
https://github.com/n8n-io/n8n/security/advisories/GHSA-hh89-3r9w-qj3j
More from n8n
8.8
CVE-2025-68613
n8n Vulnerable to Remote Code Execution via Expression Injection
10.0
CVE-2026-54309
n8n: n8n MCP Browser HTTP Transport Exposes Unauthenticated Browser-Control Sessions
10.0
CVE-2026-21858
n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling
9.9
CVE-2026-85165
n8n before 2.36.2 Expression Sandbox Bypass via SpreadElement
9.9
CVE-2026-72765
n8n before 2.32.1 Remote Code Execution via Expression Sandbox Escape