v1: Prevent directory path traversal in FileHandler #2388
Merged
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Presently
FileHandlerallows../which enables directory path traversal when aFilesendpoint is defined with a wildcard.Example API design definition:
Example exploit:
This patch updates
FileHandlerto returnErrNotFoundif a../is found inreq.URL.Path.I wanted to submit tests along with this but got stuck trying to make them work. If someone could provide guidance, I would be happy to make another attempt.
Existing tests do pass:
Additionally, I've applied this patch to a local dev instance of our app and verified the changes operates as expected. A curl request such as the one does return a 404.