CVE-2026-118678

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

Published Oct 28, 2026 CVSS 4.0 · 7.1 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction
First Time appeared N8n
N8n n8n
Weaknesses CWE-1321
CPEs cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*
Vendors & Products N8n
N8n n8n
References
Metrics cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H'}

cvssV4_0

{'score': 7.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Oct 29, 2026, 8:54 PM
Reserved
Oct 28, 2026, 5:28 PM
Status
Deferred
Published
Oct 28, 2026, 7:17 PM
Modified
Oct 29, 2026, 9:17 PM