Picture this. A company spends millions on cybersecurity—firewalls, intrusion detection, top-tier endpoint protection. But then, someone misconfigures an AWS S3 bucket, and suddenly, all that effort is worthless. Sensitive files, customer data, intellectual property—it’s all just sitting there, open for anyone who knows where to look.

This isn’t some rare, edge-case scenario. It happens far more often than you’d think. Organisations of all sizes—yes, even the big players—have accidentally left their cloud storage exposed to the internet. And when that happens, hackers don’t need to break in; they just walk through an open door.

How does this even happen?

AWS S3 is a fantastic tool—reliable, scalable, and widely used. But it’s also incredibly easy to misconfigure. S3 buckets are private by default, but a simple misstep—like granting public read access or allowing unauthorised users to list contents—can expose sensitive data. The worst part? It’s often not noticed until it’s too late.

Sometimes, it’s down to human error—developers testing something and forgetting to lock it down, or IT teams making changes without realising the impact. Other times, it’s a misunderstanding of AWS permission structures. Either way, the result is the same: a security vulnerability just waiting to be exploited.

How do hackers find open S3 buckets?

It’s shockingly easy. Hackers don’t need to brute-force their way in; they simply scan the internet looking for misconfigured buckets. There are various methods they use, and while we won’t go into technical specifics, here’s a high-level look at how they do it:

• Automated scanning tools – Attackers use scripts to look for publicly accessible AWS S3 buckets. These tools can crawl the web and test known S3 naming patterns to find exposed data.
• Search engines – Believe it or not, some misconfigured S3 buckets can be indexed by search engines. With the right queries, hackers can find open buckets using Google or other search engines.
• Guessing bucket names – Many organisations follow predictable naming conventions for their S3 buckets. If an attacker knows a company’s domain, they might try variations of that name to find a bucket that’s open.
• Leveraging leaked credentials – If a company has suffered a previous breach, attackers may already have old AWS credentials that allow them to probe for misconfigurations.

Once they gain access, hackers can steal data, plant malware, or even hold companies to ransom. And the worst part? Most organisations don’t even realise until someone tells them—or their data ends up on the dark web.

How DarkInvader helps secure AWS S3 buckets

This is where DarkInvader’s External Attack Surface Management (EASM) platform comes in. We continuously monitor the attack surface of organisations, checking for misconfigured AWS S3 buckets alongside a range of other security risks.

Our platform identifies open buckets, flags potential exposures, and alerts businesses before hackers get the chance to exploit them.

In today’s digital landscape, you don’t just need a firewall and an antivirus—you need constant visibility. If you’re using AWS S3, the question isn’t just whether your data is stored securely; it’s whether you know it’s secure.

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