Description
n8n before 1.123.69, 2.x before 2.33.4, and 2.34.x before 2.34.1 contains a regular expression denial of service (ReDoS) vulnerability in the Filter and Switch nodes, which compile user-supplied regex patterns with new RegExp() and execute them synchronously on the worker thread without complexity validation or execution timeout. A crafted regex pattern can block the worker for an extended period per data item processed, delaying other workflow executions on the same worker.
Affected products
n8n: n8n
References2
- github.com/n8n-io/n8n/security/advisories/GHSA-q3fv-295f-qfpf MitigationVendor Advisory
- www.vulncheck.com/advisories/n8n-before-redos-via-filter-and-sw… Third Party Advisory
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L - CVSS 4.0
-
5.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/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: 41 · as of 10 November 2026
- CWE
- CWE-1333
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