All vulnerabilities
CVE-2026-118678GHSA-fvv4-gmv9-xqf5

n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction

n8n-io n8nFrameworks
Open in ThreatlineRecord JSON
CVSS
7.1High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)No scoreNo FIRST EPSS score in this snapshot yet
Fixed in2.41.4Also 2.42.1CVE List
Published28 Oct 2026Updated 28 Oct 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability that allows low-privileged users to alter built-in object behaviour by saving workflows with specially named connection keys. Attackers can add keys such as __proto__ to workflow connections, which the periodic history compaction task processes, causing logins and writes to fail with server errors.

Text from CVE List

Affected versions 4

  • n8naffected: all versions before 2.41.4CVE List
  • n8nunaffected: 2.41.4CVE List
  • n8naffected: 2.42.0 before 2.42.1CVE List
  • n8nunaffected: 2.42.1CVE List

References 2