CVE-2026-33720 n8n Has Authorization Bypass in OAuth Callback via N8N_SKIP_AUTH_ON_OAUTH_CALLBACK
Attackers can hijack OAuth tokens if a specific environment variable is enabled, allowing them to execute workflows as the victim.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33720?
CVE-2026-33720 is a medium-severity authentication bypass vulnerability in N8n N8n, published on 25 Mar 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 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.
Weakness: CWE-863
Which versions are affected by CVE-2026-33720?
2 open source packages ship an affected version, including n8n. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
n8n npm | All versions | 2.8.0 |
n8n npm | All versions | 2.8.0 |
Products include N8n N8n.
How do I fix CVE-2026-33720?
Upgrade n8n to 2.8.0 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-33720 being exploited?
There is no known exploitation of CVE-2026-33720 in the wild and no public exploit code.
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Sources
Also known as GHSA-vpgc-2f6g-7w7x.