Which versions of N8n are affected by CVE-2026-33720?

Organizations using n8n should be aware of moderate risk from CVE-2026-33720, a incorrect authorization vulnerability rated CVSS 6.3. Attackers could gain access beyond their authorized level.. A patch is available.

Is there a public PoC exploit available for CVE-2026-33720?

Yes, a public proof-of-concept exploit is available for CVE-2026-33720. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-33720?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

N8n CVE-2026-33720

Q: What is the CVSS score of CVE-2026-33720?

CVE-2026-33720 has a CVSS 4.0 base score of 6.3 (Medium). CVSS vector: CVSS:4.0/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. EPSS exploitation probability: 0.0%.

EUVD-2026-15952 MEDIUM

Incorrect Authorization (CWE-863)

2026-03-25 GitHub_M

GHSA-vpgc-2f6g-7w7x

Authentication Bypass N8n

6.3

CVSS 4.0 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

6.3 MEDIUM

CVSS:4.0/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

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:4.0/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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Lifecycle Timeline

Patch released

Mar 31, 2026 - 21:13 nvd

Patch available

PoC Detected

Mar 27, 2026 - 19:38 vuln.today

Public exploit code

EUVD ID Assigned

Mar 25, 2026 - 18:32 euvd

EUVD-2026-15952

Analysis Generated

Mar 25, 2026 - 18:32 vuln.today

CVE Published

Mar 25, 2026 - 18:06 nvd

MEDIUM 6.3

DescriptionGitHub Advisory

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.

AnalysisAI

This vulnerability in n8n (an open-source workflow automation platform) is an authentication bypass in the OAuth callback handler that occurs when the N8N_SKIP_AUTH_ON_OAUTH_CALLBACK environment variable is explicitly set to true. An attacker can manipulate the OAuth state parameter verification to trick a victim into completing an OAuth flow that stores the victim's OAuth tokens in an attacker-controlled credential object, allowing the attacker to execute workflows using the victim's delegated permissions. The vulnerability affects n8n versions prior to 2.8.0 and requires non-default configuration to be exploitable, limiting its widespread impact but creating significant risk for affected deployments.

Technical ContextAI

The vulnerability is rooted in CWE-863 (Incorrect Authorization), specifically an improper authorization check in the OAuth callback handler. OAuth implementations rely on state parameters to prevent Cross-Site Request Forgery (CSRF) attacks by validating that the state returned by the authorization server matches the state originally issued to the client. In n8n, when N8N_SKIP_AUTH_ON_OAUTH_CALLBACK=true is set, the handler bypasses ownership verification of the OAuth state parameter, breaking the fundamental CSRF protection mechanism. This allows an attacker to initiate an OAuth flow, intercept the callback, and redirect the victim's authorization response to a credential object under attacker control. The affected product is n8n-io/n8n (cpe:2.3:a:n8n-io:n8n:*:*:*:*:*:*:*:*) prior to version 2.8.0.

RemediationAI

Organizations should upgrade n8n to version 2.8.0 or later, which includes the fix for OAuth state parameter ownership verification. For environments where immediate patching is not feasible, administrators should implement the following mitigations as temporary measures: disable the N8N_SKIP_AUTH_ON_OAUTH_CALLBACK environment variable entirely (return to default secure configuration), restrict network access to the n8n instance to fully trusted users and networks only, and implement additional OAuth validation at any reverse proxy or load balancer layer if one exists. Note that these workarounds do not fully eliminate the vulnerability and should be used only until patching is completed. Refer to the vendor advisory at https://github.com/n8n-io/n8n/security/advisories/GHSA-vpgc-2f6g-7w7x for detailed guidance.