CVE-2026-27495 is a critical vulnerability impacting n8n, an open source workflow automation platform. An authenticated user with permission to create or modify workflows can exploit this vulnerability in the JavaScript Task Runner sandbox, allowing them to execute arbitrary code outside the sandbox boundary. When internal Task Runners (the default runner mode) are utilized, this can lead to a complete compromise of the n8n host. Furthermore, if external Task Runners are used, attackers may gain access to or affect other tasks executed on the Task Runner.
This vulnerability has a CVSS score of 9.4, categorizing it as critical. The risk to organizations includes significant impacts on confidentiality, integrity, and availability, especially since task runners must be enabled with 'N8N_RUNNERS_ENABLED=true'. Therefore, it is imperative that users upgrade to n8n versions 2.10.1, 2.9.3, or 1.123.22 to remediate this vulnerability.
Organizations that cannot immediately upgrade should implement temporary mitigations. These include limiting workflow creation and editing permissions to trusted users only or utilizing external runner mode ('N8N_RUNNERS_MODE=external') to minimize the blast radius. However, these workarounds do not completely resolve the risk and should only be considered as short-term measures.
Given the critical nature of this vulnerability, organizations should prioritize patching immediately to prevent potential exploitation and mitigate risks to their systems.
Vulnerability Details
The official CVE description states that prior to versions 2.10.1, 2.9.3, and 1.123.22, an authenticated user could exploit the vulnerability in the JavaScript Task Runner sandbox. The vulnerability type is classified as a privilege escalation due to the ability to execute arbitrary code. The CVSS score is 9.4, indicating a critical severity level, and the affected vendor is n8n.
The vulnerability was published on February 25, 2026, and is classified under CWE-94, which relates to code injection. Users are strongly encouraged to upgrade to the specified versions to mitigate this risk.
Technical Analysis
The root cause of CVE-2026-27495 lies in the inadequate isolation of the JavaScript Task Runner sandbox, which allows authenticated users to execute arbitrary code. The attack vector for this vulnerability is network-based, with a low attack complexity, meaning that it does not require extensive technical skill to exploit.
Exploitation requires low privileges, as the attacker must be an authenticated user with workflow modification capabilities. User interaction is not required for the exploit to take place, thus increasing the risk of potential compromise.
The impacts of a successful exploitation include high confidentiality, integrity, and availability impacts, as attackers may gain full control over the n8n host and the ability to manipulate tasks executed on the system.
Risk & Impact Analysis
Organizations using n8n should consider the real-world deployment risk associated with this vulnerability. The potential for a complete compromise of the n8n host represents a significant threat, especially in environments where sensitive data is processed or stored.
Given the critical CVSS score, organizations must assess the urgency of addressing this vulnerability. The blast radius could extend beyond the n8n instance itself, especially when using internal Task Runners, making it crucial to act swiftly.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The vulnerability affects n8n versions prior to 2.10.1, 2.9.3, and 1.123.22. Organizations should ensure that they are using one of these versions or later to mitigate the risk.
Mitigation & Remediation
To mitigate the risk associated with CVE-2026-27495, organizations should upgrade to n8n versions 2.10.1, 2.9.3, or 1.123.22 immediately. If an immediate upgrade is not feasible, limiting workflow creation and editing permissions to trusted users or switching to external runner mode is recommended. These measures can help reduce the impact while a full remediation is being carried out.
For further details on task runners and their configurations, organizations can refer to the n8n documentation on application security assessment.
Detection Guidance
Organizations should monitor logs for any unusual behaviors or unauthorized modifications related to workflow creation and execution. Indicators may include unexpected task execution patterns, changes in user permissions, or attempts to access the Task Runner configuration.
AppSecure Threat Intelligence Insight
CVE-2026-27495 highlights the importance of secure coding practices, especially in environments that execute arbitrary code. This incident underscores the necessity for organizations to implement comprehensive security assessments during development and deployment phases. The use of secure configurations and strict access controls can significantly reduce exposure to similar vulnerabilities in the future.
For strategic insights on managing vulnerabilities, organizations can explore best practices in penetration testing methodology and how to establish a robust vulnerability management program to fortify defenses.
Furthermore, organizations should prioritize ongoing training for developers on secure coding practices to prevent similar vulnerabilities from being introduced in the future.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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