CVE-2026-77082

Name of the Vulnerable Software and Affected Versions n8n versions prior to 1.123.69 n8n versions 2.x prior to 2.33.4 n8n versions 2.34.x prior to 2.34.1

Description A regular expression denial of service (ReDoS) exists in the Filter and Switch nodes. The issue occurs because user-supplied regex patterns are compiled using new RegExp() and executed synchronously on the worker thread without execution timeouts or complexity validation. A specially crafted regex pattern can block the worker for an extended period for each data item processed, which delays other workflow executions on the same worker.

Recommendations Update to version 1.123.69 or later. Update to version 2.33.4 or later for the 2.x branch. Update to version 2.34.1 or later for the 2.34.x branch.