Skip to main content

n8n CVE-2026-56360

| EUVDEUVD-2026-42258 MEDIUM
Authentication Bypass by Spoofing (CWE-290)
2026-07-08 disclosure@vulncheck.com GHSA-wgjf-2hg5-2533
6.3
CVSS 4.0 · Vendor: vulncheck
Share

Severity by source

Vendor (vulncheck) PRIMARY
6.3 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/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
vuln.today AI
3.7 LOW

AC:H reflects the non-public webhook URL prerequisite (AT:P equivalent); integrity-only impact with no scope change beyond n8n accepting forged data.

3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

Primary rating from Vendor (vulncheck).

CVSS VectorVendor: vulncheck

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
X

Lifecycle Timeline

2
Analysis Generated
Jul 08, 2026 - 15:06 vuln.today
Patch available
Jul 08, 2026 - 15:01 EUVD

DescriptionCVE.org

n8n before versions 1.123.18 and 2.6.2 fails to verify HMAC-SHA256 signatures on Zendesk webhooks in the ZendeskTrigger node. Attackers who know the webhook URL can send unsigned POST requests to trigger workflows with arbitrary malicious data.

AnalysisAI

Webhook signature bypass in n8n's ZendeskTrigger node allows network-adjacent attackers who possess the webhook URL to inject arbitrary data into n8n workflows by sending unsigned POST requests. The ZendeskTrigger node omits the mandatory HMAC-SHA256 verification step that Zendesk's webhook security model requires, treating any inbound POST as a legitimate Zendesk event. This affects n8n v1.x before 1.123.18 and v2.x before 2.6.2; no public exploit or CISA KEV designation has been identified at time of analysis.

Technical ContextAI

n8n is an open-source workflow automation platform whose ZendeskTrigger node exposes an HTTP webhook endpoint intended to receive events from Zendesk. Zendesk's webhook security model uses HMAC-SHA256 signatures: each outbound request includes a signature header derived from a shared secret so that receivers can authenticate the source. CWE-290 (Authentication Bypass by Spoofing) applies because n8n omits this verification step entirely, relying implicitly on URL secrecy rather than cryptographic proof of origin. Affected CPE-equivalent ranges per EUVD-2026-42258 are n8n 0 through below 1.123.18 and n8n 2.0.0 through below 2.6.2. The CVSS 4.0 AT:P metric correctly captures that exploitation requires the attacker to have already obtained the webhook URL, which is not publicly discoverable by default but can leak through logs, referrer headers, or misconfigured infrastructure.

RemediationAI

Upgrade n8n to version 1.123.18 or later on v1.x deployments, or to version 2.6.2 or later on v2.x deployments; these are the confirmed vendor-released patched versions per the GitHub security advisory at https://github.com/n8n-io/n8n/security/advisories/GHSA-38c7-23hj-2wgq and supplemental advisory at https://www.vulncheck.com/advisories/n8n-webhook-forgery-via-unsigned-post-requests-in-zendesktrigger. If immediate patching is not feasible, disable all active ZendeskTrigger workflow nodes to eliminate the exposed endpoint - this has the side effect of stopping Zendesk event processing until the patch is applied. As a secondary compensating control, restrict access to the n8n webhook URL at the network or reverse-proxy layer by allowlisting Zendesk's published source IP ranges, though this requires ongoing maintenance as Zendesk IP ranges change and does not substitute for cryptographic signature verification.

More in N8n

View all
CVE-2026-21877 CRITICAL POC
9.9 Jan 08

n8n workflow automation (through 1.121.2) allows authenticated users to execute arbitrary code via the n8n service, with

CVE-2026-21858 CRITICAL POC
10.0 Jan 08

n8n workflow automation (1.65.0 to 1.121.0) allows unauthenticated file access through form-based workflows. A critical

CVE-2026-1470 CRITICAL POC
9.9 Jan 27

n8n has a fifth critical RCE vulnerability (CVSS 9.9) in the Expression evaluator, enabling code execution through craft

CVE-2026-33660 CRITICAL POC
9.4 Mar 25

An authenticated user with workflow creation or modification privileges in n8n workflow automation platform can exploit

CVE-2026-33665 HIGH POC
8.8 Mar 25

Authenticated n8n users can hijack administrator accounts when LDAP authentication is enabled by manipulating their LDAP

CVE-2023-27563 HIGH POC
8.8 May 10

The n8n package 0.218.0 for Node.js allows Escalation of Privileges. Rated high severity (CVSS 8.8), this vulnerability

CVE-2026-0863 HIGH POC
8.5 Jan 18

Authenticated users can exploit string formatting and exception handling in n8n's Python task executor to escape sandbox

CVE-2023-27564 HIGH POC
7.5 May 10

The n8n package 0.218.0 for Node.js allows Information Disclosure. Rated high severity (CVSS 7.5), this vulnerability is

CVE-2023-27562 MEDIUM POC
6.5 May 10

The n8n package 0.218.0 for Node.js allows Directory Traversal. Rated medium severity (CVSS 6.5), this vulnerability is

CVE-2026-33724 MEDIUM POC
6.3 Mar 25

n8n versions prior to 2.5.0 contain a critical SSH host key verification bypass in the Source Control feature that allow

CVE-2026-33720 MEDIUM POC
6.3 Mar 25

This vulnerability in n8n (an open-source workflow automation platform) is an authentication bypass in the OAuth callbac

CVE-2026-27495 CRITICAL
9.9 Feb 25

Code injection in n8n workflow automation before 2.10.1/2.9.3/1.123.22 allows authenticated users to execute arbitrary c

Share

CVE-2026-56360 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy