# The Node.js Upload Endpoint You Forgot Is a Liability

📰 Medium · JavaScript

Secure your Node.js upload endpoint to prevent malware and unexpected storage costs

intermediate Published 23 Apr 2026

Action Steps

Implement validation and sanitization of uploaded files using middleware like multer
Configure CloudFront and S3 to restrict access and prevent unauthorized uploads
Monitor storage usage and set up alerts for unusual activity
Use a library like clamav to scan uploaded files for malware
Test and simulate attacks on your upload endpoint to identify vulnerabilities

Who Needs to Know This

Backend developers and DevOps engineers can benefit from this article to ensure the security and reliability of their application's upload endpoint

Key Insight

💡 Trusting the client can lead to security vulnerabilities and unexpected costs, so it's essential to validate and sanitize uploaded files

Key Takeaways

Secure your Node.js upload endpoint to prevent malware and unexpected storage costs

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Title: # The Node.js Upload Endpoint You Forgot Is a Liability

URL Source: https://medium.com/@tommasobertocchideveloper04/the-node-js-upload-endpoint-you-forgot-is-a-liability-9c0ccd263a6f?source=rss------javascript-5

Published Time: 2026-04-23T16:43:43Z

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Apr 23, 2026

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# The Node.js Upload Endpoint You Forgot Is a Liability

**Most applications trust the client. That's exactly how malware gets in.**

---

A friend of mine runs a small SaaS. It lets users upload profile pictures and occasional documents. Nothing unusual. Standard Express server, standard multer middleware, files stored on S3 behind CloudFront.

Last month, his storage bill tripled overnight.

He checked the bucket. About 40 GB of files had been uploaded in 4

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# The Node.js Upload Endpoint You Forgot Is a Liability

Key Takeaways

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