Vulnerability · Published Jun 23, 2026 · Assigned by GitHub_M
CVE-2026-54311n8n: Merge Node SQL Mode Prototype Pollution
Medium 6.0
In plain English
A medium-severity security flaw in n8n from n8n-io. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
n8n is an open source workflow automation platform. Prior to 2.25.7 and 2.26.2, an authenticated user with permission to create or modify workflows could pollute the sandbox used by the Merge node's SQL Query mode. Because the sandbox context was cached and reused across all workflow executions on the instance, prototype mutations introduced by one user's workflow persist into subsequent Merge SQL executions belonging to other users or projects. This allowed a low-privileged attacker to intercept workflow data processed by other users on the same instance. This issue only affects multi-user n8n instances where more than one user has permission to create and execute workflows containing the Merge node in SQL Query mode. This vulnerability is fixed in 2.25.7 and 2.26.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | n8n | 2.26.2 | GHSA-9c38-2mcm-q7f7 |
| npm | n8n | 2.25.7 | GHSA-9c38-2mcm-q7f7 |
Affected products (as reported)
Weakness: CWE-488 · Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N
References
- https://github.com/n8n-io/n8n/security/advisories/GHSA-9c38-2mcm-q7f7 x_refsource_CONFIRM