Third-Party Scripts

Third-party apps such as Google Analytics, Meta Pixel, HotJar, and JQuery have become critical tools for businesses to optimize their website performance and services for a global audience. However, as their importance has grown, so has the threat of cyber incidents involving unmanaged third-party apps and open-source tools. Online businesses increasingly struggle to maintain complete visibility and control over the ever-changing third-party threat landscape, with sophisticated threats like evasive skimmers, Magecart attacks, and unlawful tracking practices potentially causing severe damage.

This article explores the challenges of protecting modern websites from third-party scripts and the security risks associated with a lack of visibility over these scripts.

Invisible to Standard Security Controls

Third-party scripts are often invisible to standard security controls like Web Application Firewalls (WAFs) because they are loaded from external sources that are not under the control of the website owner. When a website loads a third-party script, it is executed in the user's browser alongside the website's own code. This means that a WAF, which is typically placed in front of a website to inspect and filter incoming traffic, may not be able to detect and block malicious activity originating from a third-party script.

Moreover, third-party scripts often use obfuscation techniques to hide their true purpose or to evade detection by security controls. This can make it even more difficult for security controls to identify and mitigate potential threats. Therefore, it is important for website owners to take additional steps to monitor and control the behavior of third-party scripts.

The Security Risks Caused by Lack of Visibility

Lack of visibility over your third-party web apps and open-source tools can pose several security risks to an organization, including:

  1. Data breaches: Third-party apps often have access to sensitive data, and a lack of visibility over these apps can make it difficult to detect and prevent data breaches or unauthorized access to sensitive information.
  2. Malware and viruses: Third-party apps may introduce malware or viruses into your organization's systems, which can infect other systems and result in data loss or system downtime.
  3. Compliance violations: Third-party apps that are not properly vetted or do not comply with regulatory requirements can expose an organization to legal and financial risks, such as fines and lawsuits.
  4. Network vulnerabilities: Third-party apps that are integrated with an organization's systems can create network vulnerabilities that can be exploited by cybercriminals.
  5. Poor security practices: Some third-party apps may not have strong security controls in place, which can increase the risk of security incidents and data breaches.

To mitigate these risks, it is essential to have a thorough understanding of the third-party apps used by an organization and to implement strong security controls and processes, such as continuous security assessments, monitoring, and patching. Additionally, it is important to have clear policies and procedures in place for selecting, vetting, and managing third-party apps to ensure that they meet the organization's security and compliance requirements.

External/Installed Monitoring Solutions

Effective monitoring of third-party scripts requires external or installed monitoring solutions. Many businesses install security scripts on their websites to protect against known threats and vulnerabilities. However, these scripts are unable to access many third-party components like iFrames and the scripts they contain, as they are limited by browsing restrictions. While this approach of embedded monitoring was designed to increase the security of web components, it creates limitations for installed JavaScript to provide full security because these iFrames include trackers, pixels, and multiple unmanaged third-party scripts.

The lack of visibility over third-party scripts is a significant challenge for businesses as it limits their ability to map all trackers, detect data leakage, and create a working inventory of third-party apps and scripts. Critical activities, such as detecting CVE for JS frameworks, tracking pixels like Meta and TikTok, and tag misconfiguration, are limited because these components are rendered inaccessible. This limitation exposes businesses to the risk of data harvesting, which can result in lost revenue, damaged reputation, and regulatory fines.

Enhanced Visibility Achieved with External Monitoring

Embedded website monitoring solutions suffer from a lack of visibility. Therefore, an external monitoring solution might be the answer to solving this challenge. Just recently, Reflectiz, an external monitoring solution, helped a big financial services company detect suspicious activity related to the TikTok pixel. The company utilized Reflectiz on its website to monitor its security, and the solution detected unauthorized activity related to the pixel: the TikTok pixel script was accessing sensitive input data in one of their login forms. TikTok had updated its pixel, and the new version had been "painting" users on the website, accessing personal information, and transmitting the info to their servers. The Reflectiz investigation team provided clear mitigation steps to terminate the pixel's unapproved activity right away.

This case is a clear example of how monitoring your website from the outside gives you enhanced visibility over the modern attack surface, unlike installed monitoring solutions that simply don't see the full picture and are unable to effectively monitor third-party website components like iFrames, tags, and pixels.

Screenshot of the rogue Tiktok pixel detection
Screenshot of the rogue Tiktok pixel detection

Maintain watertight security against third-party scripts

So, what can you do to protect your websites from the risks associated with third-party scripts? Here are some tips:

  1. Conduct regular security audits: Regularly audit your website and third-party services to identify vulnerabilities and address them promptly.
  2. Use external website monitoring solutions: Implement website monitoring solutions that can detect suspicious activity and provide clear mitigation steps to address it.
  3. Use secure hosting: Choose a secure hosting provider that provides regular backups, monitoring, and security updates.
  4. Educate your employees: Train your employees to recognize potential threats and educate them about safe online practices.
  5. Use two-factor authentication: Require two-factor authentication for all sensitive areas of your website, such as the admin panel and checkout page.
  6. Use content security policies: Implement content security policies that restrict the types of content that can be loaded on your website.
  7. Keep software up to date: Regularly update your website's software, including any third-party services, to ensure that known vulnerabilities are patched.

In conclusion, the increasing reliance on third-party scripts has brought about new challenges to online businesses seeking to maintain the security and privacy of their users. The lack of visibility over these scripts increases the possibility of data breaches, cyberattacks, and compliance violations. To mitigate these risks, businesses need to understand the third-party apps used by their organizations and implement strong security controls and processes. External website monitoring solutions, like Reflectiz, can significantly enhance online visibility and provide clear mitigation steps to address suspicious activities related to third-party scripts.


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