Systems and methods for secure third-party data storage

A system for secure third-party data storage, the system comprising:

• an identification module programmed to identify, at the server-side computing device, a request from a client system to share access to an encrypted file stored under a user account, wherein the access to the encrypted file comprises access to unencrypted contents of the encrypted file;
• a key module programmed to identify, in response to the request, an asymmetric key pair designated for the user account, the asymmetric key pair comprising an encryption key and a decryption key that has been encrypted with a client-side key;
• a receiving module programmed to receive, from the client system, the client-side key;
• a decryption module programmed to:
• decrypt the decryption key with the client-side key;
• identify a file key used to encrypt the encrypted file, wherein the file key is encrypted with the encryption key;
• decrypt the file key with the decryption key to create an unencrypted version of the file key;
• a sharing module programmed to:
• generate a temporary encryption key;
• encrypt the unencrypted version of the file key with the temporary encryption key to create a temporary encrypted file key;
• transmit a temporary decryption key corresponding to the temporary encryption key to share the access to the encrypted file;
• at least one processor configured to execute the identification module, the key module, the receiving module, the decryption module, and the sharing module.

A non-transitory computer-readable-storage medium comprising one or more computer-executable instructions that, when executed by at least one processor of a computing device, cause the computing device to:

• identify, at the server-side computing device, a request from a client system to share access to an encrypted file stored under a user account, wherein the access to the encrypted file comprises access to unencrypted contents of the encrypted file;
• identify, in response to the request, an asymmetric key pair designated for the user account, the asymmetric key pair comprising an encryption key and a decryption key that has been encrypted with a client-side key;
• receive, from the client system, the client-side key;
• decrypt the decryption key with the client-side key;
• identify a file key used to encrypt the encrypted file, wherein the file key is encrypted with the encryption key;
• decrypt the file key with the decryption key to create an unencrypted version of the file key;
• generate a temporary encryption key;
• encrypt the unencrypted version of the file key with the temporary encryption key to create a temporary encrypted file key;
• transmit a temporary decryption key corresponding to the temporary encryption key to share the access to the encrypted file.