Zero-Day Vulnerabilities and its Impact on Business

Computer System Vulnerabilities are a serious security issue that can find its way to our computers through harmless browsing activities. This can be as simple as visiting a website, clicking on a compromised message or downloading software with compromised security protocols.


Exploited and infected malware exposes our systems, allowing unauthorized control to the hackers. The system becomes vulnerable to various anomalies and data exposure.

This article highlights the various aspects of Zero-Day Vulnerabilities, the risks involved and how to foresee their effects and take precautionary measures.

What is a Zero-Day Vulnerability

A Zero-Day Vulnerability is a software security flaw that makes any digitally connectible system vulnerable to security hacks or threats. It is usually fixable by a software vendor. This is usually classified as a weakness or bug within a system program or network that has been overlooked by the developers.

Impact of Zero-Day Vulnerabilities

Since the vulnerabilities are usually unknown to the developers or those responsible to mitigate the risk of cyber attacks, zero-day attacks can inflict a serious impact.

A Zero-Day Vulnerabilities often goes unnoticed by the software vendor. The time it takes for the vendor to become aware of it and develop a patch to prevent further exploitation is the period where hackers continue exploiting the systems, data and other nodes within the network.

Hackers can take advantage of this flaw and steal valuable data or information leading to major losses for a company.

The day when the vulnerability is identified is coined “Day Zero”. This is usually the day where the vendor kick starts efforts to find workarounds or patches. Yet, even with the release of the workarounds and fixes, the end-user’s system is still vulnerable until the fix is applied. This is a compelling reason for keeping all the applications on digital systems updated.

Impacts on Business

Significant damage:Zero-day Vulnerabilities can give hackers access to the system’s files to steal them, only to be sold on the black market.

Massive security risks:A zero-day vulnerability exposes all company data and finances to the hacker leading to the possibility of threats from multiple hackers.

Zero days to fix in a software bug: The system vulnerabilities due to zero-day often go unnoticed. The system administrators are also left with a small time window to fix the anomaly and thwart major data loss.

Bounties for identifying the vulnerability: Companies finding it difficult to identify and takedown software boundaries, are forced to announce bounties of up to $ 1,00,000 to bring the situation under control.

How to detect Zero-Day Vulnerabilities

There are several means to identify zero-day vulnerabilities. Prominent strategies among them are:

Statistics based detection: This strategy defines safe system behaviour. Any deviance from the defined standard triggers a warning. Machine learning is used to extract and continuously review previous exploit data to come up with the baseline of system vulnerability.

Signature based detection: Machine learning is adopted to analyse and assign signatures to malwares or bogus scripts. The resultanting malware database is used to identify new threats or unknown vulnerabilities.

Behaviour based detection: A strategy where the interaction of the incoming files with the targeted system is continuously monitored to identify and even foresee the possibility of malicious attacks.

Protective Measures (How to save yourself)

Update software packages to prevent cyber attacks: Adopting this technique consistently lowers the number of flaws like identifying, applying and updating patches to systems, servers, and networks as soon as they become available.
On an individual level, patch management policies should be activated as a part of incident response and remediation strategies.

Securing the gateways of email, servers, and networks: Zero-day attacks can target different parts of an organization's online infrastructure. Overlooking even the minutest factor, such as not vetting the emails from shady addresses, can give way to malware or other cyber attacks.

Enforce the principle of least privilege: The restriction of open-source penetration testing and system administration tools should be enforced at the time of vulnerability, as the threats are usually channelled through these systems.

Implementing cyber security hygiene: Encouraging a culture of cybersecurity awareness on practices such as phishing attacks, is an ideal strategy to foresee and thwart cyber attack concerns. This also involves deploying high end security risk mitigating systems that are monitored 24/7 for data security.

Execution and planning of multi-layered security defences: Additional layers of security such as, firing up of firewalls and intrusion detection systems to filter and prevent hostile traffic to the servers, minimizes the risk of cyber attacks. Such strategies, if combined with other awareness steps (eg. behaviour monitoring) can prevent dubious malware-infected programs from deployment and execution.

Responsibilities of a software vendor against Zero-Day Vulnerabilities

  1. A software vendor closely monitors core data, including a thorough investigation of Active Directory, files, Web Proxies, VPN, DNS, emails, etc. This can be critical.
  2. His/her role is to implement a least-privilege model, where data breakout is avoided.
  3. A software vendor establishes a back door for recovery of data. This requires the backing up of critical systems and a contingency plan in case of attack.
  4. Enforcing strict and updated software along with preparing the users to identify a threat or warn of an attack, is one of the major responsibilities of a software vendor against such system irregularities.

How is Zero-day used for advantage by hackers?

Hackers resort to different ploys to effectively deploy zero-day exploits basis and to wriggle inside to important parts of a system:

  • Spear phishing where emails with files like (e.g., Adobe PDFs) are attached and embedded with vulnerabilities.
  • Exploit kits whose agenda involves malvertisements with dangerous sites that host zero-day vulnerabilities that can easily switch on.

Recent News Examples

  • One of the most notorious in the history of cybercrimes is Stuxnet, a worm that has done a lot of zero-day exploits It was designed mainly to attack elements of an industrial control system (ICS).]This worm was introduced by the ‘The Shadow Brokers,' an advanced culmination of expert opportune hackers with EternalBlue, (used by the WannaCry and Petya/NotPetya ransomware families) and has remained the most stubborn one to date.
  • BlueKeep (CVE-2019-0708), another zero-day vulnerability seen mainly in remote desktop services. It made headlines in May because of its “Wormability.”This forced Microsoft to release security patches for Windows 2003 and Windows XP.

The Solution (What can be done?)

One of the prominent techniques to get some respite against zero-day vulnerabilities is Virtual Patching.

Virtual patching - What does it do?

Virtual patching or vulnerability shielding is the process that commonly complements an organization's security measures to shield it from vulnerability.

This shielding focuses on building up layers of security policies that interfere and exploit system applications, thereby acting as a countermeasure by revealing known and unknown threats.
This allows corporations to buy additional time, allowing their IT administrators to test and try remedying patches before they need to be deployed.

They are responsible for providing a shield against threats to IT infrastructures that have no patches or updates to support the issues, such as legacy systems or IoT devices.


Zero-day vulnerabilities are a threat that will be here to stay. As a developer or a system administrator, responsible to ensure the security of the application, it is your duty to continuously vet the system interaction and to identify any system abnormalities or exploitable attempts. With up to date information and a vigilant awareness, this vital security issue can be effectively managed.

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Written by
Paul Baka


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