6.3
MEDIUM CVSS 4.0
CVE-2026-33720
n8n Has Authorization Bypass in OAuth Callback via N8N_SKIP_AUTH_ON_OAUTH_CALLBACK
Description

n8n is an open source workflow automation platform. Prior to version 2.8.0, when the `N8N_SKIP_AUTH_ON_OAUTH_CALLBACK` environment variable is set to `true`, the OAuth callback handler skips ownership verification of the OAuth state parameter. This allows an attacker to trick a victim into completing an OAuth flow against a credential object the attacker controls, causing the victim's OAuth tokens to be stored in the attacker's credential. The attacker can then use those tokens to execute workflows in their name. This issue only affects instances where `N8N_SKIP_AUTH_ON_OAUTH_CALLBACK=true` is explicitly configured (non-default). The issue has been fixed in n8n version 2.8.0. Users should upgrade to this version or later to remediate the vulnerability. If upgrading is not immediately possible, administrators should consider the following temporary mitigations: Avoid enabling `N8N_SKIP_AUTH_ON_OAUTH_CALLBACK=true` unless strictly required, and/ or restrict access to the n8n instance to fully trusted users only. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

INFO

Published Date :

March 25, 2026, 7:16 p.m.

Last Modified :

March 25, 2026, 7:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-33720 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM [email protected]
Solution
Upgrade n8n to version 2.8.0 or later to fix OAuth state verification vulnerability.
  • Upgrade n8n to version 2.8.0 or later.
  • Avoid setting N8N_SKIP_AUTH_ON_OAUTH_CALLBACK=true.
  • Restrict access to trusted users only.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-33720.

URL Resource
https://github.com/n8n-io/n8n/security/advisories/GHSA-vpgc-2f6g-7w7x
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-33720 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-33720 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-33720 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-33720 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Mar. 25, 2026

    Action Type Old Value New Value
    Added Description n8n is an open source workflow automation platform. Prior to version 2.8.0, when the `N8N_SKIP_AUTH_ON_OAUTH_CALLBACK` environment variable is set to `true`, the OAuth callback handler skips ownership verification of the OAuth state parameter. This allows an attacker to trick a victim into completing an OAuth flow against a credential object the attacker controls, causing the victim's OAuth tokens to be stored in the attacker's credential. The attacker can then use those tokens to execute workflows in their name. This issue only affects instances where `N8N_SKIP_AUTH_ON_OAUTH_CALLBACK=true` is explicitly configured (non-default). The issue has been fixed in n8n version 2.8.0. Users should upgrade to this version or later to remediate the vulnerability. If upgrading is not immediately possible, administrators should consider the following temporary mitigations: Avoid enabling `N8N_SKIP_AUTH_ON_OAUTH_CALLBACK=true` unless strictly required, and/ or restrict access to the n8n instance to fully trusted users only. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-863
    Added Reference https://github.com/n8n-io/n8n/security/advisories/GHSA-vpgc-2f6g-7w7x
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.