In today’s digital landscape, where data plays a pivotal role, ensuring its security is of paramount importance. One aspect of data security that often goes overlooked is the threat posed by cached data. Although designed to improve performance and enhance user experience, cached data can also become a potential vulnerability if not appropriately handled. 


Understanding Cached Data

Before we delve into the threats, it’s essential to understand what cached data is and how it functions. Cached data refers to information stored temporarily on a device or server to expedite future access. When you visit a website or use an application, certain data elements, such as images, scripts, or files, are downloaded and stored in a cache. The cache acts as a temporary repository, allowing subsequent requests for the same data to be fulfilled quickly without the need to retrieve it from the original source. 


Common Uses for Cached Data

There are several reasons why your system may utilize data caching. Cached data allows websites and applications to enhance performance and speed. This is because the stored data eliminates the need for repetitive downloads, reducing the time it takes to load pages or execute specific functions.

Additionally, cached data helps reduce the load on servers and conserves bandwidth. The strain on servers is alleviated by serving cached content instead of retrieving it from the original source every time, leading to smoother operations and cost savings. 

From a UX perspective, cached data is part of creating a smooth user experience by delivering content swiftly and efficiently. Whether it’s a website loading quickly or an application responding instantaneously, the utilization of cached data often significantly improves user satisfaction.


Cached Data Threats

While cached data offers undeniable benefits, it also comes with potential risks that must be addressed. Whether specifically targeted by hackers or gathered by AI-powered data harvesting programs, cached data can provide hackers with a trove of valuable information. 

There are a number of ways in which cached data can be compromised. Sensitive information, such as URL histories, HTTP headers, HTML form inputs, cookies, and transaction history can all be revealed by accessing cached data. 

Even on mobile applications, cached information can be accessed through multiple entry channels. For example, user-entered words stored in the Android user dictionary can be accessed by any app without permission, potentially leading to data leaks. Additionally, passwords and usernames recorded by one app may be exploited by other apps. 

Furthermore, application screens retained in memory can be viewed by anyone with device access, allowing them to see transaction histories. Malicious apps created by hackers can also read data from retained screens of other apps, potentially accessing payment transaction history and account numbers.


Web Cache Poisoning

These types of attacks can be carried out by “web cache poisoning.” Web cache poisoning occurs when an attacker manipulates a web server and cache to serve a malicious HTTP response to unsuspecting users. Caches play a crucial role in this process by determining whether they have a cached copy of a requested resource or if they need to forward the request to the application server. 

“Cache keys” are used to identify cached pages and determine whether or not to open the page being requested. These keys consist of specific components extracted from an HTTP request, allowing the cache to fully identify the requested resource. By comparing a predefined subset of these components, known as cache keys, caches can identify equivalent requests and serve the appropriate cached response. Compromising the cache keys allows hackers to serve a bogus HTTP request, from which they can snatch critical information like usernames, passwords, and security questions. 


Potential Impacts of Cached Data Threats

While the inherent risk of losing any information stored in a cache is already significant, the implications of this threat vector go far beyond the cached data itself. When exploited, your cached data can become a backdoor into your system. 


Primary Security and Data Privacy Risks

One of the primary concerns that can result from a cached data breach is the chance of outsiders gaining unauthorized access to sensitive information. When data is stored in a cache, it becomes accessible to anyone with physical or virtual access to the device or server. This poses a significant privacy risk.

For instance, the exposure of personal or financial data through cached data can occur when multiple users share a device or when data is inadvertently cached and not properly cleared. Without proper precautions, cached data can inadvertently reveal sensitive information to unintended parties.

As we mentioned above, issues such as web cache poisoning can also be a vector by which further attacks can be mounted against your system. In addition to executing malicious code, web cache poisoning and cross-site scripting (XSS) attacks can enable the attackers to steal credentials that allow them directly into your system. 

This is a particularly critical concern for two reasons. Firstly, by using legitimate credentials to gain access to your networks and servers, any further actions carried out have the same devastating potential as insider attacks

The second significant danger of cached credential theft is more subtle. Often, attacks that target legitimate user credentials create some level of awareness of the breach, even if only after the fact. For example, while a social engineering scheme may successfully convince users to give over their credentials, security teams are often quick to point out the phony email or phone call. However, when data is stolen from a cache, the scope and very existence of the attack can go unnoticed until far too late. 

Secondary Legal and Compliance Concerns

While they are less direct consequences than the actual loss of data, legal and compliance issues are nonetheless a significant aspect of cached data threats. Any event leading to data being compromised can open your organization to noncompliance penalties. 

Depending on the nature of the captured data, these can include sanctions under the Health Insurance Portability and Accountability Act of 1996 (HIPAA) for health-related data. Other examples of data privacy regulation include GDPR for data pertaining to EU subjects and a wide range of state-specific laws, including California, Virginia, Utah, and many others


Addressing Vulnerabilities in Cached Data

To address vulnerabilities created by data caches, a holistic approach to data security is required. While firewalls and secure networks are essential elements of any complete information security plan, truly guarding data against all attacks requires secure-by-design technology or Self-Protecting-Data

As a pioneer of this approach, Sertainty redefines how information is protected to ensure data privacy where perimeters fail. Using cutting-edge protocols and embedding intelligence directly into sensitive data files or datasets, Sertainty leverages patented processes to govern, track, and defend data through the data itself. 

Instead of a file’s security being based on granted privileges to access the network directory where the file currently resides, Sertainty Self-Protecting Data files protect themselves against malicious activity immediately. With these protocols, the data remains secure even in situations where systems have been compromised. 

Truly Secure by Design Data with Sertainty

As a leader in self-protecting data, Sertainty leverages proprietary processes to ensure that even if systems are compromised or accessed from the inside, all data stored in them remains secure. 

At Sertainty, we know that the ability to maintain secure files is the most valuable asset to your organization’s continued success. Our industry-leading Data Privacy Platform has pioneered what it means for data to be intelligent and actionable, helping companies move forward with a proven and sustainable approach to their cybersecurity needs. 

As the digital landscape evolves and networks become more widely accessible, Sertainty is committed to providing self-protecting data solutions that evolve and grow to defend sensitive data. Cyber threats may continue to advance, and security perimeter breaches may be inevitable, but with Sertainty, privacy loss doesn’t have to be.