CVE-2026-56360 | n8n before versions 1.123.18 and 2.6.2 fails to verify HMAC-… | CVSS 4.0 MEDIUM

Description

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.

Metadata

CVE ID: CVE-2026-56360
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-06-20 21:16 UTC
Published: 2026-07-08 13:49 UTC
Last updated: 2026-07-08 14:26 UTC
Primary CWE: CWE-290
Authentication Bypass by Spoofing
Vendor / Product: n8n / n8n
Sources: cve.org · NVD

Severity & Metrics

4.0 MEDIUM CVSS 3.1

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
n8n	n8n	—	0 < 1.123.18, 1.123.18, 2.0.0 < 2.6.2, 2.6.2

Weakness (CWE)

CWE	Source	Description
CWE-290	cna	Authentication Bypass by Spoofing

CVSS scores (2)

Score	Severity	Version	Source	Vector
6.3	MEDIUM	4.0	cna	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
4.0	MEDIUM	3.1	cna	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N

References (2)

GitHub Security Advisory (GHSA-38c7-23hj-2wgq) https://github.com/n8n-io/n8n/security/advisories/GHSA-38c7-23hj-2wgq
VulnCheck Advisory: n8n - Webhook Forgery via Unsigned POST Requests in ZendeskTrigger https://www.vulncheck.com/advisories/n8n-webhook-forgery-via-unsigned-post-requests-in-zendesktrigger