CVE-2026-25054 is a Cross-Site Scripting (XSS) vulnerability categorized under CWE-80 and CWE-79, found in the markdown rendering component of the n8n workflow automation platform. This vulnerability affects versions prior to 1.123.9 and 2.2.1. The issue arises because the markdown renderer does not properly neutralize script-related HTML tags, allowing an authenticated user with permissions to create or modify workflows to embed malicious JavaScript code within markdown content such as workflow sticky notes. When other users view or interact with these workflows, the malicious script executes with the same-origin privileges as the n8n web application, enabling attackers to hijack user sessions or perform account takeover attacks. The vulnerability requires the attacker to have at least limited authenticated access with workflow modification rights, and victim users must interact with the malicious content, implying some user interaction is necessary. The vulnerability does not require elevated privileges beyond workflow modification, making it a significant risk in collaborative environments where multiple users have editing rights. The CVSS 4.0 score of 8.5 reflects a high severity due to the potential for confidentiality and integrity compromise, ease of exploitation (low attack complexity), and the absence of required user privileges beyond authentication. Although no known exploits have been reported in the wild, the vulnerability has been publicly disclosed and patched in versions 1.123.9 and 2.2.1. Organizations using affected versions should urgently apply these updates to prevent exploitation. The vulnerability highlights the risks of insufficient input sanitization in web applications that allow user-generated content, especially in automation platforms where workflows may be shared among users.

For European organizations, the impact of CVE-2026-25054 can be significant, particularly in sectors relying heavily on workflow automation and collaboration, such as finance, healthcare, government, and technology. Exploitation could lead to session hijacking and account takeover, potentially exposing sensitive business processes, confidential data, and internal automation logic. This could result in unauthorized actions within the automation platform, data leakage, and disruption of automated workflows critical to business operations. The vulnerability could also serve as a pivot point for further attacks within the network if attackers gain persistent access through compromised accounts. Organizations with multiple users collaborating on workflows are at higher risk due to the need for user interaction to trigger the exploit. The high CVSS score indicates a serious threat that could undermine confidentiality and integrity of organizational data and processes. Additionally, the lack of known exploits in the wild suggests a window of opportunity for defenders to patch systems before widespread attacks occur.

European organizations should immediately upgrade n8n installations to versions 1.123.9 or 2.2.1 or later to apply the official patch addressing this XSS vulnerability. Beyond patching, organizations should implement strict access controls to limit workflow creation and modification permissions to trusted users only, reducing the attack surface. Employ Content Security Policy (CSP) headers to restrict script execution and mitigate the impact of potential XSS payloads. Conduct regular security reviews of user-generated content handling and markdown rendering components in internal applications. Educate users about the risks of interacting with untrusted workflows and encourage vigilance when opening shared automation workflows. Implement monitoring and alerting for unusual activity within the n8n platform, such as unexpected workflow modifications or suspicious user behavior. Consider network segmentation to isolate critical automation infrastructure and reduce lateral movement opportunities in case of compromise. Finally, maintain an up-to-date inventory of affected software versions and apply security updates promptly.