CVE-2026-33720 json
n8n Has Authorization Bypass in OAuth Callback via N8N_SKIP_AUTH_ON_OAUTH_CALLBACK
published 7mo ago modified 4mo ago also EUVD-2026-15952 , GHSA-vpgc-2f6g-7w7x
- cvss
- 4.2
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 7%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm n8n 2.8.0
- n8n n8n 2.8.0
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- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.3 | 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 |
| GitHub | 3.1 | 4.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 4.0 | 6.3 | 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 |
| NVD | 3.1 | 4.2 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | n8n | <2.8.0 |
2.8.0 |
Affected products
- n8n-io n8n
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
github.com
/n8n-io/n8n/security/advisories/GHSA-vpgc-2f6g-7w7x
web, mitigation, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-33720
advisory
-
github.com
/n8n-io/n8n
package
Sources
- CVE List CVE-2026-33720
- GitHub Advisory GHSA-vpgc-2f6g-7w7x
- NVD CVE-2026-33720
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.