CVE-2026-54311: n8n Merge Node SQL Mode Prototype Vulnerability

MODERATE
Advisory Identifier: GHSA-9c38-2mcm-q7f7
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CVSS 6.3
CWE-488
Published
Advisory Summary

CVE-2026-54311 is a MODERATE (CVSS 6.3) merge node sql mode prototype vulnerability (CWE-488: Exposure of Data Element to Wrong Session) affecting n8n libraries in the npm ecosystem. The issue involves merge node sql mode prototype pollution. Remediation is available by upgrading affected packages to version 2.26.2, 2.25.7.

CVE-2026-54311 at a Glance

CVE Identifier CVE-2026-54311
GHSA Identifier GHSA-9c38-2mcm-q7f7
Severity MODERATE
CVSS v3.1 Base Score 6.3
CWE Classification CWE-488: Exposure of Data Element to Wrong Session
Affected Product n8n
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 6.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Changed (S:C)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-54311

To remediate this vulnerability, upgrade all affected n8n dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

n8n fixed: 2.26.2 
npm install n8n@2.26.2
n8n fixed: 2.25.7 
npm install n8n@2.25.7
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls n8n

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-54311, inspect your project dependencies using npm:

npm ls n8n

Analyze the terminal output to locate any version of n8n in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.26.2), your application is affected.

Note: The npm ls n8n command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-488: Exposure of Data Element to Wrong Session, where the product does not sufficiently enforce boundaries between the states of different sessions, causing data to be provided to, or used by, the wrong session. In n8n, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

## Impact 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. ## Patches The issue has been fixed in n8n versions 2.25.7, and 2.26.2. Users should upgrade to one of these versions or later to remediate the vulnerability. ## Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Limit workflow creation and editing permissions to fully trusted users only. - Disable the Merge node by adding `n8n-nodes-base.merge` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

CVE-2026-54311 Affected n8n Versions

2 component(s)
Fixed Versions:
2.26.22.25.7
Product / Package Ecosystem Affected Versions Fixed Version
n8n
npm/n8n
npm
≥ 2.26.0
< 2.26.2
2.26.2
n8n
npm/n8n
npm
< 2.25.7
2.25.7

References

GitHub Advisory / Wiki ADVISORY
https://github.com/n8n-io/n8n/security/advisories/GHSA-9c38-2mcm-q7f7
NVD — CVE-2026-54311 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54311
n8n Source Repository REPOSITORY
https://github.com/n8n-io/n8n

Frequently Asked Questions

What is CVE-2026-54311?
CVE-2026-54311 is a security vulnerability in n8n involving Merge Node SQL Mode Prototype Pollution under CWE-488: Exposure of Data Element to Wrong Session.
Which n8n versions are affected?
Affected versions include releases prior to 2.26.2, 2.25.7 across affected packages: n8n.
What version fixes CVE-2026-54311?
Upgrading to 2.26.2, 2.25.7 (or the latest patched release for your respective branch) resolves the vulnerability.
Is n8n affected?
Yes, n8n is affected in releases prior to 2.26.2, 2.25.7. Upgrade your dependency to 2.26.2, 2.25.7 or later.
What is the CVSS score of CVE-2026-54311?
CVE-2026-54311 has a CVSS v3.1 base score of 6.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N.
What CWE is associated with CVE-2026-54311?
CVE-2026-54311 is classified under CWE-488: Exposure of Data Element to Wrong Session (The product does not sufficiently enforce boundaries between the states of different sessions, causing data to be provided to, or used by, the wrong session.).
How can I check npm dependencies for CVE-2026-54311?
Run the dependency tree command: 'npm ls n8n'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-9c38-2mcm-q7f7",
  "modified" : "2026-07-20T13:39:32Z",
  "published" : "2026-06-16T19:01:16Z",
  "aliases" : [ "CVE-2026-54311" ],
  "summary" : "n8n: Merge Node SQL Mode Prototype Pollution",
  "details" : "## Impact\nAn 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.\n\nThis 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.\n\n## Patches\nThe issue has been fixed in n8n versions 2.25.7, and 2.26.2. Users should upgrade to one of these versions or later to remediate the vulnerability.\n\n## Workarounds\nIf upgrading is not immediately possible, administrators should consider the following temporary mitigations:\n- Limit workflow creation and editing permissions to fully trusted users only.\n- Disable the Merge node by adding `n8n-nodes-base.merge` to the `NODES_EXCLUDE` environment variable.\n\nThese workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "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"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "n8n"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.26.0"
      }, {
        "fixed" : "2.26.2"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "npm",
      "name" : "n8n"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.25.7"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/n8n-io/n8n/security/advisories/GHSA-9c38-2mcm-q7f7"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-54311"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/n8n-io/n8n"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-488" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-16T19:01:16Z",
    "nvd_published_at" : "2026-06-23T16:17:02Z"
  }
}