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Corrupting Source Image

container-security-image-security-registry | Level: Easy  | Total Lab Runs: 0 | Free Lab

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Lab Walkthrough Video:

The target docker server is running a webserver image that is serving on port 80. The docker image used for the webserver is stored on the unprotected private docker registry present on the same network. A watchtower instance deployed on the target server ensures that the latest image present in the private repository is used for webserver container. A flag is mounted from the host machine into /tmp directory of the webserver container.

Objective: Leverage this arrangement to retrieve the flag from the webserver container!


  • This lab is dedicated to you! No other users are on this network :) 
  • Once you start the lab, you will have access to a Ubuntu docker host terminal instance.
  • The target docker server can be accessible on "targetserver" domain. 
  • The private registry can be accessed on "registry" domain on port 5000.

1. Flag

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  • Attacking the lab infrastructure

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