How to Reduce The Most Common SFTP Security Risks

Sharing files is essential for business operations, with employees frequently transferring documents, reports, and spreadsheets to colleagues, clients, and stakeholders. However, methods like file transfer protocol (FTP) and secure file transfer protocol (SFTP) are not one hundred percent secure, posing risks from unsecured plain-text emails, unencrypted file transfers, and server vulnerabilities.

We’ll explore the most important file transfer security risks and evaluate the question: “How secure is SFTP?” We’ll also share best practices to strengthen SFTP security, emphasizing encryption to protect sensitive data.

Ready to get started? Here are the 10 most common file transfer security risks:

1. Weak SFTP authentication methods

FTP, initially developed as a basic protocol for moving files across networks, is far from secure by today’s standards. While it's adequate for non-sensitive, internal transfers, the lack of encryption leaves both files and credentials exposed during transit, making them vulnerable to interception.

The solution: hardened authentication

Use secure FTP versions like FTPS (FTP with TLS encryption) and SFTP (FTP over secure shell, or SSH). Both options add critical encryption layers, providing extra security to files and credentials as they move across networks.

With layering encryption methods, data is protected from unauthorized access, ensuring that secure file transfers are resistant to vulnerabilities.

2. Hardware and software misconfiguration

Misconfigured hardware and software can open doors to vulnerabilities, especially when outdated or incorrectly set up. While many email servers today support transport layer security (TLS) encryption, not all are configured to use it.

The solution: constant security audits and remediation

Regular security audits are essential for ensuring your servers maintain the latest TLS encryption standards. Audits help identify and address configuration errors before they become security risks, enhancing the safety of file transfers.

3. SFTP servers exposed to the network in the DMZ

Isolating file transfer servers from external networks is crucial to protect data integrity. Many organizations set up SFTP servers within a demilitarized zone (DMZ) to manage data transfer securely between external networks and internal systems.

However, this sometimes requires the server to be exposed for external connections, increasing vulnerability, especially when using protocols like AS2, which combines HTTP-based connections with encrypted message transfers.

The solution: file encryption with reverse proxy gateway

For robust file transfer security, employ a layered approach. Implement firewall rules to restrict access to trusted internet protocols and encrypt data within the DMZ to deter unauthorized access. A reverse proxy gateway adds an additional layer by routing external requests to internal servers without direct exposure, collectively enhancing SFTP security and ensuring data remains protected during transfers across networks.

4. Unsecured scripting

Automated file transfers are often accomplished using custom scripts, but these can lack essential security measures, especially in basic protocols like FTP. Hardcoded plain-text passwords are common in these scripts, which create a significant security threat, risking unauthorized access.

The solution: managed file transfer

Switching from scripts to a managed file transfer (MFT) solution enhances security with multi-factor authentication, centralized management, and end-to-end encryption. MFT solutions automate secure transfers, reducing risks of interception and unauthorized access, making SFTP safe and reliable with robust encryption and access controls.

5. Unsecured open-source clients

While open-source SFTP clients may offer encryption and user authentication, they often lack advanced security features required in enterprise environments. Open-source tools might have infrequent updates, and their wide accessibility often means they lack the stringent security measures required for large-scale file transfers, intensifying vulnerabilities.

The solution: enterprise-grade SFTP (yes, it does exist)

Enterprise-grade SFTP solutions enhance protection with features like multi-factor authentication, centralized security management, and permission-based access. Opting for an MFT solution ensures that files are encrypted and securely managed before they are transferred.

These solutions receive regular updates, minimizing security vulnerabilities. This level of protection facilitates secure file transfer through SFTP, even in complex enterprise environments.

Learn more about CData’s enterprise-grade SFTP.

6. Shared private keys

Sharing private keys within an organization is common but can compromise even the best SFTP server setups. Shared private keys gives multiple individuals access to sensitive files, risking unauthorized access if the keys fall into the wrong hands.

The solution: secure certificate management

A file transfer solution with integrated certificate management mitigates the vulnerabilities associated with shared private keys by implementing strict access controls, so each user has a unique set of credentials. This centralized approach to key management reduces the risk of unauthorized access.

Moreover, integrated certificate management automates the process of issuing, renewing, and revoking certificates, significantly improving operational efficiency.

7. Outdated, vulnerable server and/or SFTP software

Using outdated file transfer software introduces vulnerabilities into your protocol, making sensitive data more susceptible to breaches. Outdated servers or unsupported SFTP software lack the security patches needed to protect against new threats, leaving your data at risk.

The Solution: regular software updates

To keep your SFTP server secure, it’s essential to maintain up-to-date software and install patches as they become available. Regularly updating SFTP servers and software reduces vulnerabilities, ensuring your file transfer protocol is well protected. Additionally, limit application programming interface (API) endpoint access to authorized users only, minimizing potential breaches from outdated or unsupported software.

8. Corrupted server system

If all file transfers rely on a single server, this setup creates a central point of failure that could result in significant data loss if the server is compromised.

The solution: regular data backups and syncs

A secure file transfer solution with regular backups and tested recovery processes, along with automatic data synchronization capabilities, helps protect critical files and minimizes the risk of data loss due to server corruption. Organizations can quickly restore lost data, mitigating the impact of server failure and enhancing the resilience of SFTP.

9. The person handling the file transfers leaves your organization

The unexpected departure of the individual that manages file transfers can disrupt operations, especially if processes are undocumented or scattered across tools. This poses a significant risk in organizations reliant on one person’s expertise, potentially rendering file transfer processes obsolete and jeopardizing critical operations.

The solution: documented workflows and supported, centralized processes

To mitigate disruptions, ensure all file transfer workflows are well-documented, including access, file paths, protocols, and special requirements. Centralizing these processes with a protocol like SFTP simplifies knowledge transfer during personnel changes and ensures business continuity.

10. Keeping the lights on

Maintaining file transfer operations is challenging for IT teams, particularly during unexpected issues. Technical problems can cause downtime, delays, or data loss, especially without troubleshooting support. This stress is compounded when technical assistance for specific file transfer tools is limited.

The solution: a secure file transfer tool with excellent support

Choose a file transfer solution with strong, responsive customer support to ensure assistance is available when needed. A reliable support team can quickly resolve technical issues, maintaining the security of essential file transfers and minimizing interruptions.

Managed file transfer: Simplify integration and reduce risks with CData Arc

Companies increasingly rely on MFT solutions to centralize, automate, and secure essential file transfers. Read our guide to find out how CData Arc can streamline integration, enhance security, and reduce the risks associated with standard file transfers.