GCP - Cloudbuild Privesc

👉 Overview

👀 What ?

GCP CloudBuild Privesc is a method used to escalate privileges in the Google Cloud Platform's (GCP) CloudBuild service. This escalation can allow a user to gain unauthorized access or permissions within the cloud environment.

🧐 Why ?

Understanding GCP CloudBuild Privesc is crucial for both developers and security professionals. For developers, it's essential to be aware of potential security vulnerabilities when designing and implementing cloud-based applications. Security professionals, on the other hand, need to understand these vulnerabilities to effectively protect the systems they are tasked with securing.

⛏️ How ?

To implement GCP CloudBuild Privesc, a user would typically exploit a weakness or loophole in the CloudBuild service's security. This could involve manipulating permissions, injecting malicious code, or exploiting a weakness in the system's configuration. It's important to note that implementing such a method for malicious purposes is illegal and highly discouraged.

⏳ When ?

The practice of privilege escalation, including methods like GCP CloudBuild Privesc, has been around as long as multi-user computer systems have existed. However, with the advent of cloud computing and services like GCP's CloudBuild, these methods have evolved and become more sophisticated.

⚙️ Technical Explanations

GCP CloudBuild Privesc works by exploiting the way GCP's CloudBuild service handles permissions. When a build is initiated, it uses the permissions of the user who initiated it. However, if the build's configuration allows it, the build can assume a service account's permissions. This can be exploited by a malicious user who has permissions to edit build configurations but not execute certain actions. By editing the build configuration to use a service account with higher permissions, they can execute those actions indirectly through the build. To mitigate this threat, it's important to follow the principle of least privilege when assigning permissions and to carefully control who has the ability to edit build configurations.