Summary
n8n: Authenticated Users Can Exhaust Temporary Disk Storage via Data-Table File Uploads
Workarounds
If upgrading is not immediately possible, administrators should consider the following temporary mitigations:
- Restrict n8n instance access to fully trusted users only.
- Set
uploadMaxFileSizeto a low value to limit individual upload size. - Monitor and alert on disk usage in the n8n temporary upload directory.
These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
Impact
An authenticated user can repeatedly upload files to the data-table upload endpoint, bypassing the per-request quota check, which does not account for files already written to the shared temporary directory. This causes temporary files to accumulate on disk until the periodic cleanup runs, potentially exhausting available disk space on the host.
The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap. Typical impact: resource exhaustion leading to denial of service.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
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. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Users should upgrade to the patched version once available to remediate the vulnerability.
Frequently Asked Questions
- What is CVE-2026-58661? CVE-2026-58661 is a medium-severity allocation of resources without limits or throttling vulnerability in n8n (npm), affecting versions >= 2.0.0, < 2.28.0. It is fixed in 2.28.0, 1.123.58. The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap.
- Which versions of n8n are affected by CVE-2026-58661? n8n (npm) versions >= 2.0.0, < 2.28.0 is affected.
- Is there a fix for CVE-2026-58661? Yes. CVE-2026-58661 is fixed in 2.28.0, 1.123.58. Upgrade to this version or later.
- Is CVE-2026-58661 exploitable, and should I be worried? Whether CVE-2026-58661 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
- What actually determines whether CVE-2026-58661 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.
- How do I fix CVE-2026-58661?
- Upgrade
n8nto 2.28.0 or later - Upgrade
n8nto 1.123.58 or later
- Upgrade