Description
n8n before 1.123.83, 2.41.4, and 2.42.1 contains a server-side request forgery vulnerability in the Slack Trigger webhook that allows unauthenticated attackers to exfiltrate Slack tokens by bypassing signature verification when no signing secret is set. Attackers who know the webhook URL can name a file to download, causing the node to send the workspace access token to an attacker host and return the response.
References2
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:H/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 - EPSS — exploit probability
- 0% percentile: 20 · as of 3 November 2026
- CWE
- CWE-918
Could this be exploited in your environment?
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