CVE-2026-118678
n8n before 2.41.4 and 2.42.1 Prototype Pollution DoS via Workflow History Compaction
CVSS Score
7.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-1321 |
| Vendor | n8n-io |
| Product | n8n |
| Published | Oct 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
High
Affected Versions
n8n-io / n8n
0 < 2.41.4
n8n-io / n8n
2.42.0 < 2.42.1
References
Credits
🔍 Masofgon