n8n - Webhook Forgery via Unsigned POST Requests in ZendeskTrigger
Collected exploitation and prediction evidence
Risk source coverageCISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.
No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.
cve-program · CVE-2026-56360
Publishedn8n 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.
- Source published
- 8 Jul 2026 13:49:03 UTC
- Source modified
- 8 Jul 2026 14:26:33 UTC
- Observed here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.
CVSS 4.0 · 6.3 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
CVSS 3.1 · 4.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
euvd · EUVD-2026-42258
Publishedn8n 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.
EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.
Original publisher date fields
datePublished: Jul 8, 2026, 1:49:03 PM
dateUpdated: Jul 8, 2026, 2:26:33 PM
1 related source bulletins · separate from aliases
NCSC-2026-0248: Kwetsbaarheden verholpen in n8n workflow automation platform
CVE-2026-27493 · CVE-2026-27494 · CVE-2026-27495 · CVE-2026-27497 · CVE-2026-27498 · CVE-2026-27577 · CVE-2026-27578 · CVE-2026-56357 · CVE-2026-56350 · CVE-2026-56360 · CVE-2026-56349 · CVE-2026-56353
- Source published
- Jul 8, 2026, 1:49:03 PM (timezone not stated)
- Source modified
- Jul 8, 2026, 2:26:33 PM (timezone not stated)
- Observed here
- 7 Nov 2026 12:35:44 UTC
- Source terms
- ENISA EUVD · source terms and attribution apply
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.
EUVD CVSS 4.0 · 6.3 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
nvd · CVE-2026-56360
Publishedn8n 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.
NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
Source analysis status: Analyzed
Weakness classifications: CWE-290
Original publisher date fields
published: 2026-07-08T14:17:16.757
lastModified: 2026-10-25T20:10:00.147
1 source CPE criteria · context only
- cpe:2.3:a:n8n:n8n:*:*:*:*:*:node.js:*:*
The original JSON retains the logical configuration operators, exclusions and version bounds.
- Source published
- 8 Jul 2026 14:17:16 UTC
- Source modified
- 25 Oct 2026 20:10:00 UTC
- Observed here
- 27 Oct 2026 15:15:18 UTC
- Source terms
- NIST NVD usage terms; underlying source attribution retained
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.
CVSS 4.0 · [email protected] · Secondary · 6.3 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
CVSS 3.1 · [email protected] · Secondary · 4.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
osv · GHSA-38c7-23hj-2wgq
Published## Impact An attacker who knows the webhook URL of a workflow using the ZendeskTrigger node could send unsigned POST requests and trigger the workflow with arbitrary data. The node does not verify the HMAC-SHA256 signature that Zendesk attaches to every outbound webhook, allowing any party to inject crafted payloads into the connected workflow. ## Patches The issue has been fixed in n8n versions 2.6.2 and 1.123.18. Users should upgrade to one of these versions or later to remediate the vulnerability. ## Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Limit workflow creation and editing permissions to fully trusted users only. - Restrict network access to the n8n webhook endpoint to known Zendesk IP ranges. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
- Source published
- 26 Feb 2026 22:47:06 UTC
- Source modified
- 9 Jul 2026 04:11:38 UTC
- Observed here
- 24 Oct 2026 13:17:17 UTC
- Source terms
- GitHub Advisory Database · CC-BY-4.0
Original source record · Cite this exact observation · Complete original publisher JSON
This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.
CVSS_V3 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
CVSS_V4 · 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
Publisher rating · MODERATE