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user-data

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You will hopefully find this site is well-secured and I'm not interested in being hacked. I'm interested in learning about how people try to hack me, though.

What is this endpoint?

user-data

Cloud-init user-data path that can contain bootstrap scripts and secrets

What an attacker could do

Cloud-init user-data frequently contains bootstrap scripts with embedded secrets, SSH keys, or credentials; retrieval (e.g., via SSRF to the metadata endpoint) hands an attacker instance provisioning details.

How to defend it

Avoid embedding secrets in user-data, enforce IMDSv2 to block SSRF-based metadata access, and never expose cloud-init artifacts through the web server.

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Learn More

Want to dive deeper into this topic? Check out the official documentation.

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