CVE-2026-25056: n8n Merge Node Arbitrary File Write Vulnerability - What It Means for Your Business and How to Respond
A critical vulnerability in the popular open-source workflow automation platform n8n threatens organizations that rely on it to connect systems, automate processes, and leverage AI-driven workflows. Disclosed in February 2026, CVE-2026-25056 enables authenticated users with workflow editing permissions to write arbitrary files to the server, potentially achieving remote code execution.
Businesses across North America using self-hosted n8n deployments face significant exposure if they have not updated. This post explains the business implications, helps you determine if you are affected, and outlines clear actions to protect operations, data, and compliance posture. IntegSec recommends immediate assessment for any organization using n8n for mission-critical automations.
n8n serves as a flexible, extensible alternative to proprietary automation tools, enabling teams to build complex workflows that integrate applications, databases, APIs, and AI services. Many organizations in the United States and Canada deploy it on-premises or in private clouds to maintain data control.
Security researchers reported the issue, which centers on the Merge node's SQL Query mode. It allows users with legitimate permissions to create or modify workflows to perform unauthorized file writes on the n8n server. The vulnerability received a CVSS v4.0 base score of 9.4 (Critical), reflecting its network attack vector, low complexity, and high impacts on confidentiality, integrity, and availability.
n8n maintainers disclosed it on February 4, 2026, alongside patches in versions 1.118.0 and 2.4.0. The timeline underscores the need for prompt patching in environments where internal users or compromised accounts could exploit workflow editing features.
If your organization uses n8n to automate business processes, this vulnerability puts core operations at risk. An attacker who gains authenticated access—through phishing, credential compromise, or an insider—could exploit a workflow to write malicious files and execute code on your server. This could disrupt automated processes that handle customer data, financial transactions, supply chain logistics, or internal compliance reporting.
Data breaches represent a primary concern. Compromised n8n instances could expose sensitive information processed in workflows, leading to regulatory violations under laws such as CCPA, HIPAA, or Canadian privacy regulations. Recovery costs, legal fees, and notification requirements add financial strain.
Reputation damage follows quickly when customers learn of automation platform compromises, especially in sectors like fintech, healthcare, or manufacturing where trust is paramount. Downtime from exploited systems halts revenue-generating processes and erodes confidence among partners.
Compliance teams face added pressure. Auditors increasingly scrutinize automation tools as part of the attack surface. Unpatched vulnerabilities like this one can result in findings that delay certifications or trigger insurance reviews. For mid-sized to enterprise organizations in the US and Canada, the combination of operational disruption and potential data loss makes proactive remediation essential.
Financial Services Disruption: A regional bank relies on n8n to automate loan processing workflows between core banking systems and document repositories. A compromised employee account allows an attacker to inject malicious files via the Merge node. This leads to data exfiltration and temporary suspension of automated approvals, delaying customer services and triggering regulatory reporting obligations.
Healthcare Operations Impact: A mid-sized clinic network uses n8n for patient data synchronization and appointment reminders. Exploitation enables code execution that corrupts workflow integrity, potentially exposing protected health information. The incident requires forensic investigation, patient notifications, and enhanced controls to restore HIPAA-compliant operations.
Manufacturing Supply Chain Breakdown: A Canadian manufacturer depends on n8n to orchestrate inventory updates and supplier integrations. An attacker leverages the vulnerability to disrupt production scheduling workflows, causing shipment delays and inventory inaccuracies that affect downstream partners and revenue forecasts.
Professional Services Exposure: A US-based legal firm automates document review and client onboarding processes with n8n. Successful exploitation leads to unauthorized access to case files, resulting in confidentiality breaches, client attrition, and potential malpractice concerns.
If any of these statements apply to your environment, take immediate action to verify and remediate.
Strengthen your defenses against vulnerabilities like CVE-2026-25056 by partnering with experts who understand both automation platforms and enterprise risk. Contact IntegSec today for a comprehensive penetration test of your n8n deployments and broader cybersecurity posture. Our team delivers actionable insights that reduce risk without disrupting operations. Visit https://integsec.com to schedule your assessment and secure your critical workflows.
The root cause lies in insufficient sanitization and path validation within the Merge node's SQL Query mode implementation. This allows authenticated users with workflow modification rights to craft inputs that result in arbitrary file writes to the n8n server's filesystem. The attack vector is network-based, typically via the n8n web interface or API when creating or updating workflows.
Affected components include the node execution logic handling SQL query operations in versions prior to the patched releases. Attack complexity remains low, requiring only low privileges (PR:L) and no user interaction beyond standard workflow editing. The CVSS 4.0 vector is AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H, with CWE-434 (Unrestricted Upload of File with Dangerous Type) and CWE-693 (Protection Mechanism Failure) classifications.
NVD reference: https://nvd.nist.gov/vuln/detail/CVE-2026-25056. Successful exploitation grants attackers the ability to place webshells or other malicious payloads, leading to remote code execution on the host.
Version Enumeration:
Bash
# Check n8n version via API or UI curl -s http://your-n8n-instance:5678/version | jq # Or check package.json / container image tagsScanner Signatures: Look for detections targeting n8n Merge node SQL mode anomalies or known vulnerable version patterns in tools like Nuclei or custom OpenVAS checks.
Log Indicators: Monitor for unusual workflow save events involving Merge nodes with anomalous SQL query payloads containing file paths or suspicious content. Check server logs for unexpected file creation in n8n data directories.
Behavioral Anomalies: Watch for new processes spawned from n8n runtime, unexpected network connections from the n8n server, or modifications to files outside expected workflow storage. Network indicators include large or malformed POST requests to workflow endpoints.
For environments unable to patch immediately, use official workarounds such as blocking specific nodes and enforcing strict permission models as documented in n8n resources.