VPN Security for Banking Apps: Risks and Protection

Using banking applications through VPNs from questionable providers, even when configured on a router, is not secure, despite traffic encryption. Although the VPN provider doesn’t have direct access to the device, they can perform network-level attacks, including session interception and packet manipulation, creating serious risks for banking operations.

Contents

• Main risks of using VPNs from questionable providers
• Attack mechanisms when using VPN on a router
• Why even encrypted traffic doesn’t guarantee security
• Practical recommendations for secure banking service usage
• Technical aspects and security limitations

Main risks of using VPNs from questionable providers

Even when configured on a router, using unreliable VPN providers creates significant threats to banking application security. Key risks include:

• Traffic interception and modification: Despite encryption between the device and VPN server, the provider has full access to all outgoing traffic. An attacker can analyze user behavior patterns, transaction timestamps, and other metadata.

• DNS-level attacks: Some VPN services may redirect DNS requests through their servers, allowing the provider to control which websites the user visits and potentially redirect them to phishing sites.

• Log and data retention: Many questionable VPN providers actively collect and store information about user actions, creating a risk of confidential banking data leakage.

It’s important to note that even without direct device access, the VPN provider controls all of the user’s network activity, making it a vulnerable link in the chain of banking operation security.

Attack mechanisms when using VPN on a router

When using a VPN configured on a router, an attacker controlling the VPN service can carry out several types of attacks:

1. Session-level attacks

Although modern banking applications use multi-layer encryption, including TLS 1.3, there are attacks that can be performed even with certificates:

• Protocol version downgrade: Some vulnerable implementations may be configured to use older TLS versions that are susceptible to attacks.
• Handshake attacks: An attacker can manipulate the connection establishment process to weaken encryption.
• Delayed encryption attacks: In some cases, it may be possible to obtain information before a secure connection is fully established.

2. Application-level attacks

Even with encrypted network traffic, some attacks can be performed at the application level:

• User behavior analysis: An attacker can monitor patterns of banking application usage, which helps in planning more targeted attacks.
• Coordination with other attacks: Information collected through the VPN can be used in combination with other attack methods, such as phishing or malware.

Why even encrypted traffic doesn’t guarantee security

Many users mistakenly believe that traffic encryption completely eliminates risks. However, there are several scenarios where encryption can be bypassed or weakened:

1. Certificate issues

Although modern applications verify certificates, there are ways to bypass this verification:

• Trusted certificate attacks: Some corporate or government organizations may have legitimate certificates that can be used for MITM attacks.
• PKI infrastructure attacks: In rare cases, attacks on the root certification system are possible.
• Certificate verification vulnerabilities: Some applications or operating systems may have vulnerabilities in the certificate verification process.

2. Attacks on specific protocols

Even when using modern encryption protocols, some attacks may be effective against specific implementations:

Example of an SSL Strip attack:
1. The attacker blocks HTTPS connections
2. Redirects the user to HTTP versions of sites
3. The user enters data in unencrypted form

3. Endpoint attacks

The most serious vulnerability is that encryption only protects traffic between the device and the server. If an attacker controls both the VPN provider and the bank’s servers, they can completely control the communication.

Practical recommendations for secure banking service usage

To minimize risks when using banking applications, follow these practical security measures:

1. Choosing reliable VPN providers

When it’s necessary to use a VPN for banking operations:

• Choose providers with a transparent logging policy (zero logs)
• Prefer companies with security audits from independent organizations
• Avoid free VPN services, as they are most often data collection tools

2. Additional protection measures

• Use two-factor authentication for all banking operations
• Regularly update your operating system and applications
• Use antivirus software with anti-phishing features
• Monitor bank accounts for unauthorized transactions

3. Alternative solutions

For secure remote access to banking services:

• Use official mobile applications from banks
• When remote access is needed, use virtual private networks from recommended providers
• Consider using hardware tokens for transaction confirmation

Technical aspects and security limitations

Session interception and command sending capability

Regarding your specific question about the possibility of session interception and command sending:

Technically possible are several attack scenarios:

1. Session-level attacks: An attacker can intercept and store encrypted session data, and then attempt to decrypt it when they have computational power or vulnerabilities in encryption algorithms.

2. Authentication protocol attacks: Some authentication protocols may be vulnerable to replay attacks.

3. Timing attacks: An attacker can delay or modify timestamps, which can lead to session synchronization issues.

Limitations of current protection systems

Modern banking systems have several layers of protection, but none are absolutely reliable:

Technical limitations of attacks

Despite the theoretical possibility of attacks, there are significant limitations in practice:

• Modern encryption algorithms (AES-256, ChaCha20) require enormous computational power to crack
• Banking transaction monitoring systems can detect unusual activity
• Multi-factor authentication makes it difficult to capture control of a session

Sources

1. Official documentation on banking application security from the Central Bank of Russia
2. VPN security guide from National Institute of Standards and Technology (NIST)
3. Research on mobile banking application vulnerabilities from Positive Technologies
4. Global financial services cybersecurity overview from PwC
5. Recommendations for secure VPN usage from Electronic Frontier Foundation (EFF)

Conclusion

Using banking applications through VPNs from questionable providers poses significant security risks, even when configured on a router. The main threats include traffic interception, DNS-level attacks, and potential session manipulation. Despite data encryption, there are several scenarios where attackers can access confidential information or even control banking operations.

Security recommendations:

• Use only verified VPN services with transparent policies
• Apply multi-factor authentication for all banking operations
• Regularly update software on devices
• Monitor transactions and immediately report suspicious activity

For maximum security in banking operations, it’s recommended to use official mobile banking applications without intermediate VPN services of questionable origin.