A computer-implemented method for protecting platform-as-a-service platforms may include 1) identifying a platform-as-a-service platform that is configured to allow installations of third-party application packages, 2) intercepting a third-party application package in transit to the platform-as-a-service platform for installation, 3) extracting metadata from the third-party application package, and 4) applying a compliance policy to the third-party application package to determine whether to allow an installation of the third-party application package on the platform-as-a-service platform based on the metadata. Various other methods, systems, and computer-readable media are also disclosed.