CVE-2025-46343

Credit

We would like to thank @Mahmoud0x00 for reporting this issue.

n8n workflows can store and serve binary files, which are accessible to authenticated users. However, there was no restriction on the MIME type of uploaded files, and the MIME type could be controlled via a GET parameter. This allowed the server to respond with any MIME type, potentially enabling malicious content to be interpreted and executed by the browser.

An authenticated attacker with member-level permissions could exploit this by uploading a crafted HTML file containing malicious JavaScript. When another user visits the binary data endpoint with the MIME type set to text/html, the script executes in the context of the user’s session. This script could, for example, send a request to change the user’s email address in their account settings, effectively enabling account takeover.

Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.

CVE-2025-46343 has a CVSS score of 5.0 (Medium). The vector is requires local access, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.90.0); upgrading removes the vulnerable code path.

Kodem intelligence

• [email protected]

1. What is CVE-2025-46343? CVE-2025-46343 is a medium-severity cross-site scripting (XSS) vulnerability in n8n (npm), affecting versions < 1.90.0. It is fixed in 1.90.0. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
2. How severe is CVE-2025-46343? CVE-2025-46343 has a CVSS score of 5.0 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of n8n are affected by CVE-2025-46343? n8n (npm) versions < 1.90.0 is affected.
4. Is there a fix for CVE-2025-46343? Yes. CVE-2025-46343 is fixed in 1.90.0. Upgrade to this version or later.
5. Is CVE-2025-46343 exploitable, and should I be worried? Whether CVE-2025-46343 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2025-46343 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2025-46343? Upgrade n8n to 1.90.0 or later.