Are SSH Keys or Passwords Better for SFTP Authentication? (2024)

FAQs

Are SSH Keys or Passwords Better for SFTP Authentication? ›

Neither SSH keys nor passwords are completely immune to compromise. There's no one option that's foolproof. However, if you're not sure which one to use, we recommend using SSH keys alongside a password to authenticate your users against an SFTP server.

From a security standpoint, using SSH-keys to authenticate a user's identity leads to greater protection of your data. Username/password authentication can often lead to security compromises, in particular, brute force attacks by hackers.

The SSH key acts as a more secure and efficient alternative to traditional password-based authentication. This is because keys are less likely to be guessed or brute-forced compared to passwords. However, it is highly recommended to protect your private key with a passphrase.

SSH vs SFTP: Key Differences

SSH is designed primarily for secure remote command execution, while SFTP provides secure file transfer capabilities. In terms of security, both SFTP and SSH have equal firewall compatibility and security due to their shared protocol foundation.

SSH key pairs offer a more secure way of logging into your server than a password that can easily be cracked with a dictionary and brute force attacks. SSH keys are very hard to decipher with these attacks.

2 Benefits of keys

Using keys for SSH authentication has several advantages over passwords. First, keys are more resistant to hacking, since they are harder to guess or steal than passwords. Second, keys can enable passwordless login, which saves time and avoids typing errors.

Most Secure: Hardware Keys

External hardware keys, like Yubikeys, are among the strongest authentication factors available.

Benefits of SSH Key Authentication

This means anyone eavesdropping on the traffic, such as by packet sniffing, would not be able to improperly access and decrypt transmitted data. SSH is also resistant to brute force attacks and protects against certain attack vectors used to gain access to remote machines.

SSH requires some software and settings to use, and it may not be compatible with some older or simpler devices. SSH also requires some knowledge and skills to use properly, such as generating and managing keys, choosing encryption algorithms, or troubleshooting errors.

Unlike symmetric encryption (which uses the same key to encrypt and decrypt), SSH key authentication employs asymmetric encryption algorithm, where the encryption and decryption use different keys. A user (or an authorised person) needs to generate both private key and a public key.

Do you need a SSH key for SFTP? ›

There's no one option that's foolproof. However, if you're not sure which one to use, we recommend using SSH keys alongside a password to authenticate your users against an SFTP server.

Your SSH keys can then serve as SFTP keys. Simply put, SSH keys and SFTP keys are the same. That said, file transfer solutions that offer SFTP do not necessarily provide SSH functionality.

SFTP cannot exist without SSH — SFTP uses SSH as the binding agent to transfer files securely. In other words, SSH protocol is used in the file transfer mechanism SFTP. In fact, most SSH servers include SFTP capabilities. However, not all SFTP servers support SSH commands and actions.

Key vs password

Passwords are often created to be memorized by users and may contain non-random information such as dictionary words. On the other hand, a key can help strengthen password protection by implementing a cryptographic algorithm which is difficult to guess or replace the password altogether.

With SSH keys, if someone gains access to your computer, the attacker can gain access to every system that uses that key. To add an extra layer of security, you can add a passphrase to your SSH key. To avoid entering the passphrase every time you connect, you can securely save your passphrase in the SSH agent.

Create an sFTP connection using SSH keys:

Select the FTP connector from the list of connectors. Enter the Host URL of the FTP server, and select the sFTP protocol. Enter the username. Paste the RSA private key you generated into the Authentication Key (pem format) field.

Public key authentication provides cryptographic strength that even extremely long passwords can not offer. With SSH, public key authentication improves security considerably as it frees the users from remembering complicated passwords (or worse yet, writing them down).

They are generally considered to be more secure than traditional passwords, as they cannot be guessed or stolen. Finally, physical tokens are also becoming increasingly popular for passwordless authentication. These are physical devices, such as key fobs or USB keys, that can be used to authenticate.

SSH key authentication is also more convenient than password authentication. The keys connect users and processes to a server by initiating authentication and granting access automatically, so users don't have to remember or enter their password for each and every system.

Two-Factor Authentication

This makes it much more difficult for someone to gain access to your account, even if they have your password. 2FA is not foolproof, but it is more secure compared to using only username and password. This makes it a valuable tool to help keep your account safe.