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VoIP Hacking: How It Works & How to Protect Your VoIP System

VoIP Hacking

Unlike the traditional telephone system that requires cable connections in your office or business premises, a voice over internet protocol (VoIP) telephone system relies on the internet to make calls using internet-enabled devices.

Many organizations that handle a huge volume of phone calls prefer the VoIP telephone system because it is cost-effective, reliable, portable, and offers multi-functional features.

According to research, companies can cut communication costs by up to 75% when they choose VoIP.

However, IP telephony poses a security risk to a company’s sensitive data due to the possibility of VoIP hacking. This is because everything happens over the internet and uses cloud storage.

This article explores the subject and discusses everything you need to know and how to tell if you’ve been hacked.

What Is VoIP Hacking?

So, what is the dreaded ‘VoIP hacking?’ It is any criminal attack employed by hackers to infiltrate or steal data from your business phone system.

Typically, hackers target your VoIP telephone systems to eavesdrop on calls, steal critical information about your company and your customers, and even make international calls, racking up huge bills.

The attacks on the IP telephony systems usually happen when a business insider gives information to scammers unknowingly. Consequently, cybercriminals take control of your VoIP phone system.

Mostly, the infiltration to your company’s phone system is a gateway for other criminal activities. These may include getting details for impersonating your company, charging your credit cards, and accessing sensitive and private clients’ information.

Types of VoIP Hacking

Due to their dependence on the internet and different setup compared to the traditional telephone systems, VoIP systems face unique security risks.

Below are five kinds of VoIP hacking you should know:

1. Unauthorized use

This phone system attack involves hackers using your company’s phone network to call people or organizations pretending to be you.

Criminals use auto-dialing software and robocalling with your IP telephony system. Those who answer to your phone ID receive a pre-recorded message prompting them to do specific things.

For example, recipients may be asked to input their credit card details to verify their accounts supposedly. However, it is not your company calling but the criminals using your line.

Hackers can access a lot of sensitive information using this technique. This way, they conduct fraudulent activities using your legitimate business phone service.

Since it is your caller ID that recipients see when hackers are using your VoIP phone, the criminals can impersonate your business to obtain customers’ private information.

What’s worse, this hacking can go undetected, more so if you use a DIY VoIP phone setup.

Fortunately, you can arrest this hacking by regularly monitoring your call logs and history and setting the system to notify you if you hit a specific limit.

2. Toll Fraud

Since international calls are pretty expensive to make, hackers make those calls, and the bills are charged to your account. This is referred to as toll fraud.

The attackers target admins and system users with phishing scams to get unauthorized access to your company’s VoIP system.

A possible way hackers can get access is by leaving a voicemail to a department in your business asking them to confirm some information like bank details.

If your employees respond to the call and pass the verification codes, like IP address and the phone system password, unsuspecting they are hackers, the criminals will get access.

With the necessary information in their hands, the attackers hack your internet-based phone system. After that, they make unauthorized use of your VoIP system to call long-distance numbers piling up huge bills on your account.

3. Spoofing

Typically, most people trust their caller ID. However, caller ID might not be the best way to know where a call is coming from.

Sometimes hackers can call your business using a fake caller ID and take advantage of the trust you place on a familiar or local phone number. The attackers can then leverage the fake ID with another criminal technique like social engineering.

Your staff will usually give attention to calls from specific names or numbers. Therefore, if the ID shows the call is from a trusted person or business, for instance, your VoIP provider, they may unknowingly expose sensitive information.

Sharing crucial details by unsuspecting employees could enable hackers to access your company’s cloud-based phone system.

4. Eavesdropping

Did you know that attackers can listen to your business calls or recordings, such as voicemails, without you knowing? As a result, you need to put in place measures to prevent the possibility of criminals’ eavesdropping on voice communications on your VoIP system.

However, eavesdropping can only happen when your data is unencrypted, orthereach on the local network.

Using insecure networks, characterized by a lack of Real-time Transport Protocol (SRTP) and Transport Layer Security (TLS), is a loophole that could enable attackers to keep their prying eyes on the network.

Through eavesdropping, hackers could gather information about your company, clients, and other parties. The worst bit is they can get content even from all recordings.

Some risks that could arise from eavesdropping include hackers:

  • Accessing your clients’ information and selling it
  • Selling your intellectual property to your rivals
  • Blackmailing your company with sensitive information

5. Social engineering

Social engineering leverages human interaction rather than the VoIP system technicalities. Because your staff generally like to be friendly and have no basis for turning down any request they deem harmless, they might unknowingly give the attacker information for future crimes.

One factor that promotes this hacking technique is the poor execution of social engineering campaigns. Most companies hardly educate their employees on the risk of fraudulent phone calls made by potential attackers disguising their callers’ IDs.

Criminals use tricky means to get information about a target and can use those details later. For example, they could use the information to request data, like asking you to verify your account. Hackers could also harass victims depending on the data they have.

Due to the calls that seem urgent and without suspecting any malicious intentions, your staff members bow to the pressure and give information through social engineering scams.

Signs That Your VoIP System Has Been Hacked

Although you can enjoy incredible benefits from using VoIP phone systems, for instance, reducing costs by up to 80%, there is a sharp increase lately in attempts to hack these phone networks.

Stats from RedShift Network indicate that corporate clients experience more than 40,000 varying VoIP/SIP attacks daily.

Here are three signs that show your VoIP system may have been hacked:

A sudden increase in phone bills

When your company uses VoIP, you should pay far lower phone bills, not more. Thus, investigate if there are any substantial sudden rises in the amount you’re billed.

If the bill has increased without matching the volume of users or calls your business makes, your IP telephony system has probably been hacked.

As much as you may want to overlook that and see it as a minor thing, it is a red flag.

Unknown numbers in VoIP call history

Do you regularly go through your call history? If you do not, you better start now because it is one of the most effective ways to know if your business’ cloud-based phone system has been compromised.

If you identify calls to numbers outside your database, especially numbers from other countries, you need to be more careful and investigate.

When you notice the strange calls appear more frequently in your call log, hackers may have attacked you.

Increase in off-work calls

If you start realizing that there are calls on your IP phone system outside working hours, the most likely explanation is that your VoIP has been compromised.

This emphasizes the need to monitor your call log history frequently. It can help you to unearth VoIP hacking.

How to Protect Your VoIP System from VoIP Hacking

Your business can suffer significant monetary losses from VoIP hackings, not to mention losing the trust of your clients and wasting a lot of time trying to get back on track.

Fortunately, your company can eliminate or thwart the majority of VoIP vulnerabilities by sensitizing employees about them, having regular education sessions on cloud-based telephony security, and acting early to reinforce its defenses.

Below are 11 strategies that can help protect your company from VoIP hacking:

1. Choose the right VoIP provider

The provider you choose plays a huge role in your VoIP phone’s security. Therefore, it’s important that you make a solid assessment of your security needs based on the sensitivity of the data that will be shared through phone calls.

Additionally, find out the system precautions that the provider has in place to repel attacks. The key prevention measures you need to look for in a provider are VoIP traffic tracking and notifications for suspicious incidents or activities.

With this in mind, you’ll need to research those providers that offer features that cater to those specific needs. For example, ULTATEL provides a wide range of security features, including physical security, fire control, backup power, system redundancy, and 24/7 network monitoring.

2. Control administrator access

Any person with administrative rights to access your VoIP infrastructure controls everything on your internet-based phone system.

Admin permissions allow you to set up new lines, join conference calls, manage bills, and access all data, which might result in intrusions with severe outcomes.

You have to consider the staff members who will get admin permissions carefully. Avoid allowing people who do not need access to have it.

Also, the fewer employees who have administrator access, the better it is to reduce social engineering attacks. While people commit mistakes, if they have lower-level permissions, the impact of the errors is minimized.

3. Use VPN

If you have remote staff, they have to keep in touch with their colleagues and customers through phones, exposing them to VoIP hacking.

To safeguard against phone system attacks, you can make it mandatory for all employees to install VPN on their work machines, smartphones, and softphones.

A virtual private network (VPN) strengthens the connection between a remote employee’s device and your VoIP phone system, the same way you could have a strong network in the office.

In addition, your workers should avoid using public WiFi networks. Instead, they should use a secure private network. This can almost entirely keep off hackers who could eavesdrop on your remote team’s calls.

4. Monitor your calls and access logs

Your call log shows the day and time of each call, the number of calls to specific IDs, and the calls’ location.

Regular scrutiny of the call log can help you identify your regular call activity. Any unusual interaction may be an indicator of a hack.

Also, viewing your VoIP access log can help catch intrusion, for instance, if you spot a strange IP address or you notice an employee with administrative access had signed in during off-work hours.

5. Regularly check your VoIP system

You shouldn’t just leave your VoIP system to do its job after it’s been set up. You need to check its status and functions constantly.

You can spot weaknesses and holes in your phone system’s security by doing regular checks. Also, administrators need to evaluate access frequently to thwart compromise.

Your IT department also needs to conduct annual penetration tests simulating attacks to establish if the system is secure. If there are weaknesses, they should be fixed as soon as possible.

6. Use strong passwords and change them regularly

During the installation of your VoIP solution, you get a default password from the provider to start off. You need to change the default password ASAP.

On top of that, you should make your employees aware of the strong password best practices. It would be best to sensitize them about the dangers of using simple or the most common passwords and using similar passwords across accounts.

Using repeated passwords (credential stuffing) implies a hacker can access other systems if they crack the passcode for one of them. Thus, each system’s password needs to be unique.

Also, passwords need to be changed regularly to prevent any team members who no longer work with you from accessing the system and other malicious actions.

7. Enable 2FA

Hackers are too clever these days to be deterred by robust passwords only. Therefore, to strengthen VoIP security and withstand hack attempts to your VoIP system, users need an extra layer of protection: two-factor authentication.

You need to validate your login attempts to your IP telephony system by:

  • Using an authenticator app to scan a QR code
  • Recording yourself verbalizing a secret code
  • Using a fingerprint identification

The above extra authentication features ensure hackers cannot access your cloud-based phone system, even when they crack your password. The system is only accessible to those having the proper second-step credentials.

Given that a single weak point in your telephone system can expose you to VoIP hacks, you and your employees need to be well-informed about cybersecurity trends.

Additionally, if you have staff members who are not aware of threats, they might make a mistake that can lead to a costly data breach.

One way to ensure maximum security awareness from staff is to educate them on cybersecurity practices since onboarding. You must emphasize the essence of strong passwords and common security challenges that need to be prevented.

Moreover, ensure they have a VPN installed on their devices. Regular training sessions on cybersecurity are also necessary.

9. Have a device management policy

Ensure your staff’s equipment has the best security measures in place to avoid exposure of your company’s phone system to potential attackers.

Having a device management policy will allow you to reduce staff risk on your phone system, especially if they use their devices for business calls. For example, such a policy might include:

  • Keep software on personal devices up-to-date if they are used for business.
  • Connecting all devices to a secure WiFi network.
  • Having fingerprint ID on all smartphones for unlocking them.
  • Immediate reporting of any lost, stolen, or misplaced device.
  • Have a daily routine for checking cybersecurity compliance.

10. Prepare a response plan in case a breach occurs

Although you may have implemented top-notch security measures in your company, hackers can still crack them and infiltrate your system.

Therefore, you need to have a well-detailed response plan in case there’s a data breach. The document should list what your company will do if an attack happens to avoid the situation worsening due to confusion, and not knowing what to do.

Also, a disaster recovery plan is another crucial document. It outlines the steps to follow to recover any information lost and mitigate the impact of any worst-case scenarios.

11. Regularly update your VoIP OS and firmware

Some avoidable hackings occur because you and your staff are lax in updating VoIP operating systems and firmware.

The software developer may have identified some weaknesses that regular updates could solve. Therefore, ensure your business phone OS and firmware are frequently updated.

The good news is that your staff can do most of the updates because the systems have the update features and may prompt the updating when necessary. It can also be scheduled so it doesn’t interfere with working hours.

However, if your staff cannot update the system or devices, seek your provider’s assistance.

Summary and Takeaways

The VoIP phone system has many benefits for businesses, including:

  • Cost-effectiveness
  • Portability
  • Reliability
  • Multi-functional features like teleconferencing, instant messaging, video conferencing, voicemails, faxes, etc.

Because everything related to VoIP is stored in the cloud, you need to have measures to protect your VoIP phone systems from different types of hacking. The various kind of VoIP hacking include:

  • Unauthorized use
  • Toll fraud
  • Eavesdropping
  • Spoofing
  • Social engineering

You can protect your VoIP system from VoIP hacking through:

  • Choosing the right VoIP provider
  • Controlling administrator access
  • Monitoring your call and access logs
  • Using VPN
  • Enabling a 2 Factor-Authentication
  • Using strong passwords and changing them frequently
  • Regularly checking your VoIP system
  • Staying on top of Cybersecurity trends

Unlike traditional landline phone systems, VoIP systems rely on a reliable internet connection to provide voice and other communications features. This makes VoIP systems inherently more reliable, robust, portable, and cost-effective compared to traditional phone systems.

Unfortunately, because VoIP systems rely on the internet, they also have inherent security risks and can be hacked. If they are, the results could be devastating. Hopefully, this post helped illustrate how VoIP hacking works and how you can avoid it when using a VoIP system.

If you want a VoIP system that protects your data, get in touch with ULTATEL. Our cloud-based phone systems have all the security features you need to keep your, and your customers’ data, safe.

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