@satishbh Also to add more context to this for others who come across it (using the older version):
https://github.com/june07/nodebb-plugin-cloudstorage/issues/2#issuecomment-526089881
The root cause of the error was having an S3 bucket that wasn't public. The plugin then handled the thrown error by the S3 API incorrectly, which was fixed in:
marvin-zhao created this issue in june07/nodebb-plugin-cloudstorage closed Aws s3 don't work #2 0 committed to june07/nodebb-plugin-cloudstorage Fix https://github.com/june07/nodebb-plugin-cloudstorage/issues/2I found the reason that my bucket wasn't public.