Zombie Data: The Scary Truth About Old, Unprotected Data and How to Lay it to Rest

This Halloween, there is something creepy lurking in the shadows, haunting companies long after it has been forgotten. But it’s a different kind of menace than what horror movies want us to imagine. It’s zombie data — old, unprotected data that’s no longer needed but hasn’t been securely managed or disposed of. And many businesses are unaware of the risks posed by it. This data can be a major security risk, a drain on resources, and a potential compliance nightmare. But there are ways to lay it to rest for good.

What is Zombie Data?

Zombie data is data that is no longer actively used but still exists on company servers, devices, or in cloud storage. It’s not part of daily operations, but it’s lurking in the shadows, forgotten and unmanaged. As harmless as it may seem, this “zombie” data can come back to haunt a business in unexpected ways. 

Zombie data doesn’t appear out of nowhere — it’s typically a byproduct of day-to-day operations, past projects, or inefficient data management practices. Here are a few of the main culprits:

Backups That Never Get Deleted

Companies often create backups to safeguard against data loss. However, these backups can become “stale” over time, sitting in storage long after the data they protect is no longer needed. Without a clear backup management or deletion policy, these backups can become zombie data, inflating storage costs and creating unnecessary risks.

Employee Turnover

When employees leave, they leave behind documents, emails, and project files. If these aren’t properly archived or deleted, they remain in the system indefinitely. In addition to wasting storage space, these old files can contain sensitive information that becomes vulnerable to unauthorized access if not properly secured.

System Migrations and Upgrades

During IT system upgrades or data migrations, old files are often left behind, especially if they weren’t correctly classified or prioritized for migration. Companies may keep old data “just in case,” but if left unmanaged, these files can become both a burden and a risk.

Inadequate Data Lifecycle Policies

A common issue for many companies is not having a clear data lifecycle management policy in place. Without a strategy to define when and how data should be archived, deleted, or otherwise disposed of, companies inadvertently create zombie data. This data lingers on servers and in storage, contributing to data clutter that makes active management harder.

Without proper data maintenance and data hygiene policies, companies could unwittingly be harboring servers full of unstructured zombie data that hasn’t been accessed in years but is still vulnerable to attack.

Why Zombie Data is a Security Threat

When left untouched, zombie data is waiting, lurking in the shadows, until the moment where a cybercriminal takes advantage of it and that forgotten data comes back to haunt the company who forgot about it. Zombie data can pose a serious cybersecurity threat to organizations if left unchecked.

Firstly, outdated data may lack the same security protections or monitoring as active data. This makes it a prime target for cybercriminals. While zombie data may be unimportant for day-to-day tasks in a company, the data itself can still be highly valuable for cybercriminals, with the data often including personal or sensitive information.

Additionally, storing large volumes of unused data can drive up cloud storage costs and slow down overall data management, reducing operational efficiency. Not only is the storage of zombie data costly, but it can also put companies at risk for data protection regulations like GDPR, PIPEDA, or CCPA, especially if the data is unencrypted or unmanaged. 

Companies often overlook the risks posed by zombie data, thinking that if it’s out of sight, it’s out of mind. However, these forgotten files, old records, and legacy databases are exactly the types of weaknesses that attackers seek out, and they present compliance and operational challenges that can weigh down any business.

Identifying and Managing Zombie Data

By understanding the risks and taking action to address zombie data, companies can prevent these risks from haunting their future and ensure they’re not paying the price for data they no longer need. Here are some steps that companies can take to protect themselves from zombie data:

Conduct a Data Audit

The first step is to conduct a data audit. This means looking through all systems, devices, storage solutions, and backup locations to understand what data exists and where it’s stored. Map out all sources of data within the organization including databases, servers, cloud storage, hard drives, and physical archives. Any of these locations may have outdated or redundant data. 

Assess how often each type of data is accessed and by whom. Data that hasn’t been accessed in a long time or is associated with inactive users is likely a candidate for archival or deletion. Data that is being used should be assigned to a set of data owners. These data owners should take responsibility over the data and provide insight into whether it is still relevant or can be disposed of securely. 

Classify and Prioritize

The next step is to classify and prioritize data by sensitivity, age, and relevance to determine whether it is worth keeping or should be deleted. Sensitive data could, for example, be data that includes personally identifiable information or financial records and should be prioritized. Organizations should define how long each type of data should be retained, with a minimum and maximum number of years for certain types of data to meet regulatory compliance. 

Secure Data Disposal

After identifying and prioritizing zombie data, the next step is to ensure that it’s securely deleted or archived to minimize risk. Secure data disposal requires proper tools and processes to prevent any chance of unauthorized access or data leakage.

For files stored on physical devices like hard drives or servers, data shredding tools can ensure that data is permanently erased. If devices containing zombie data are no longer in use, consider certified disposal methods, like physical shredding or crushing, to prevent data recovery. For cloud or digital storage, deletion protocols that meet regulatory standards such as wiping data from backup locations should be employed instead. 

Automate Data Management

Lastly, implementing automation can significantly reduce the burden of managing data over the long term. Automated data management policies help ensure data is regularly reviewed, classified, and disposed of according to pre-set criteria. Companies can set up rules to automatically archive, delete, or move data based on age, relevance, or usage.

Data Lifecycle Management (DLM) tools can also be used to manage the entire lifecycle of data, from creation to archiving and disposal. Similarly, real-time monitoring helps identify when data is accessed, modified, or flagged for review, which can help give IT teams visibility into data usage and make it easier to detect and address zombie data before it piles up.

Wrapping up

Zombie data is more than just digital clutter; it’s a lurking threat with the potential to compromise security, inflate costs, and expose companies to compliance risks. But the good news is that with the right approach, zombie data can be brought under control. With well-defined data retention and disposal policies, businesses can prevent zombie data from returning, keeping storage lean and secure.

Don’t let zombie data haunt your business. For companies looking to establish a sustainable data management strategy, consider partnering with IT experts who can guide you in securing your data and meeting compliance standards. With the right tools and support, organizations can create a safe, compliant, and efficient data ecosystem, free from the risks posed by forgotten, unmanaged data.