CVSS 4.0
8.8 highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:L/SC:H/SI:H/SA:LCVE-2026-42235
High (8.8) in n8n n8n. EPSS 0.3% chance of exploitation in the next 30 days. Fixed in n8n 1.123.32, 2.17.4, 2.18.1.
n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, an unauthenticated attacker could register a malicious MCP OAuth client with a crafted client_name. If a victim user authorized the OAuth consent dialog and a second user subsequently revoked that access, a toast notification would render the injected script. Clicking the link would execute arbitrary JavaScript in the victim's authenticated n8n browser session, enabling credential and session token theft, workflow manipulation, or privilege escalation. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.
Severity
CVSS 3.1
9.6 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H- EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 26% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-79, CWE-87
- Published
- Modified
- Record from
- the NVD, synced
Affected
- n8n:n8n
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-537j-gqpc-p7fq | npm | n8n | <1.123.32 | 1.123.32 |
| GHSA-537j-gqpc-p7fq | npm | n8n | >=2.18.0 <2.18.1 | 2.18.1 |
| GHSA-537j-gqpc-p7fq | npm | n8n | >=2.17.0 <2.17.4 | 2.17.4 |