CVE-2026-77082 n8n-io CVE debrief

Who should care

DevOps teams using n8n for workflow automation, security teams responsible for monitoring and protecting workflow systems, and administrators managing n8n deployments should be aware of this vulnerability and take steps to mitigate it.

Technical summary

The n8n workflow automation tool contains a regular expression denial of service (ReDoS) vulnerability in its Filter and Switch nodes. These nodes compile user-supplied regex patterns using new RegExp() and execute them synchronously on the worker thread without complexity validation or execution timeouts. An attacker could craft a regex pattern that, when processed, blocks the worker thread for an extended period, delaying other workflow executions on the same worker. This issue affects n8n versions before 1.123.69, 2.x before 2.33.4, and 2.34.x before 2.34.1.

Defensive priority

Organizations using n8n should prioritize patching to prevent potential ReDoS attacks.

Recommended defensive actions

• Inventory and triage of n8n instances
• Patch n8n to version 1.123.69 or later, 2.33.4 or later, or 2.34.1 or later
• Implement compensating controls such as workflow monitoring and timeouts
• Restrict user input for regex patterns in Filter and Switch nodes
• Monitor for suspicious workflow execution delays

Evidence notes

The CVE-2026-77082 record indicates a ReDoS vulnerability in n8n versions before 1.123.69, 2.x before 2.33.4, and 2.34.x before 2.34.1. The vulnerability is located in the Filter and Switch nodes, which compile user-supplied regex patterns synchronously without validation or timeout. A crafted regex can cause extended worker thread blocking, delaying other workflow executions.

Official resources