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Zero-day exploit: A type of cyber attack that needs your attention

Published on: May 23, 2025

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Zero-day exploit: A type of cyber attack that needs your attention Zero-day exploit: A type of cyber attack that needs your attention

In recent years, cyber threats have become increasingly sophisticated and often invisible until it’s too late. One of the most dangerous and elusive of them all is the zero day exploit. At Vi, we understand how critical digital security is for both individuals and organisations. That’s why we’re diving into what a zero day attack is, how it works, and why you need to stay vigilant, especially while travelling or relying on digital infrastructure across borders.

Whether you’re an IT professional, a business traveller, or simply someone who uses their smartphone to manage personal banking or emails, knowing about zero day vulnerability is more important now than ever before.

What exactly is a zero-day exploit?

A zero-day exploit refers to a cyber-attack that takes advantage of a security flaw unknown to the software or hardware vendor. Since developers have had "zero days" to fix the vulnerability, there’s no patch or update available to protect users at the time of attack, making it incredibly dangerous.

Cybercriminals exploit these weaknesses to install malware, steal data, or gain unauthorised access to systems. A zero-day attack can compromise devices without leaving obvious signs, and because the vulnerability is unknown to the manufacturer, it can remain active for weeks or even months before being patched.

Examples of zero-day attacks

There have been several examples of zero-day attacks over the years that have caused significant disruption. One of the most notorious was Stuxnet, a 0 day exploit that targeted Iran’s nuclear programme back in 2010. It used multiple zero-day vulnerabilities to sabotage centrifuges, setting a precedent for cyber warfare.

Another major incident was the 2017 WannaCry ransomware attack, which took advantage of a Windows zero-day vulnerability. It affected over 200,000 computers across 150 countries, including major hospitals and government systems. Then there’s the 2021 Microsoft Exchange Server breach, where attackers exploited several zero-day vulnerabilities to access email accounts and data from thousands of organisations.

These high-profile breaches show how damaging a zero-day exploit attack can be and how fast it can spread when left unchecked.

How zero-day attacks work

A typical zero-day attack unfolds like this: a hacker discovers a previously unknown vulnerability in software, be it in an operating system, browser, or third-party plugin. Instead of reporting it to the vendor, they craft a piece of malware or malicious code to exploit the flaw. In some cases, this information is sold on the dark web to other cybercriminals, adding fuel to the fire.

Once the zero-day exploit is deployed, it can steal sensitive data, spy on users, or hijack systems. Because traditional antivirus tools may not yet recognise the threat, detection can be delayed, leading to serious consequences for users and enterprises alike.

How to protect yourself from zero-day exploit attacks

Unfortunately, defending against a zero-day exploit attack isn’t straightforward, given that there’s often no patch available when it first emerges. However, the following steps can help reduce your exposure:

  • Regularly update all software:

    The faster you apply security patches and updates, the less time vulnerabilities remain open for exploitation.
  • Use reputable security tools:

    Advanced antivirus and endpoint protection systems can detect unusual behaviour linked to zero-day exploit attacks.
  • Practice good digital hygiene:

    Avoid clicking on unknown links or downloading files from untrusted sources.
  • Use a secure internet connection, and this is where we, at Vi, come in.

Why Vi’s International Roaming plans are a smart choice for digital safety

When travelling abroad, many people connect to public Wi-Fi networks in hotels, airports, or cafes, often unaware that these can be hotspots for cybercriminals. A compromised network can be a perfect gateway for launching a zero-day attack or distributing malware without your knowledge. By staying connected through your own secure mobile network rather than public Wi-Fi, you automatically reduce the chances of falling victim to a zero-day exploit while overseas. We believe that staying secure should be effortless, and that’s exactly what our roaming services aim to provide. Here are some of our top prepaid and postpaid International Roaming plans that offer great internet, SMS, and calling services:

Prepaid:

Price

Validity

Benefits

₹3495

7 days

Unlimited Data, Unlimited Outgoing (Local + To India) & Incoming Calls, ₹15/Outgoing SMS, Available in 124 countries.

₹4695

10 days

Unlimited Data, Unlimited Outgoing (Local + To India) & Incoming Calls, ₹15/Outgoing SMS, Available in 124 countries.

₹5195

14 days

Unlimited Data, Unlimited Outgoing (Local + To India) & Incoming Calls, ₹15/Outgoing SMS, Available in 124 countries.

 

Postpaid:

Price

Validity

Benefits

₹749

24 hours

Unlimited Incoming & Outgoing Calls, Outgoing Calls (Local & to India), Rest of the World Calls ₹35/min, Unlimited Data, Available in 144 countries.

₹3999

10 days

Unlimited Incoming & Outgoing Calls, Outgoing Calls (Local & to India), Rest of the World Calls ₹35/min, Unlimited Data, Available in 144 countries.

₹4999

14 days

Unlimited Incoming & Outgoing Calls, Outgoing Calls (Local & to India), Rest of the World Calls ₹35/min, Unlimited Data, Available in 144 countries.

₹5999

30 days

Unlimited Incoming & 1500 Outgoing Mins, Outgoing Calls (Local & to India) (after 1500 Mins ₹3/Min), Rest of the World Calls ₹35/Min, Unlimited Data (High Speed 30GB, throttled to 64kbps thereafter), Available in 144 countries.

 

The future of zero-day vulnerabilities

As technology continues to evolve, so will the methods used by cyber attackers. Artificial intelligence and machine learning are already being used to detect threats faster, but they’re also being used by attackers to create smarter, more targeted exploits. New examples of zero-day attacks emerge every year, targeting everything from smartphones and routers to cloud infrastructure and IoT devices. This is why organisations around the world invest heavily in bug bounty programmes and cybersecurity R&D to catch vulnerabilities before they’re exploited.

A 0 day exploit is not just a technical glitch; it’s a ticking time bomb in the hands of those who know how to use it. The best defence is awareness, vigilance, and the right tools, including secure connectivity when travelling. We urge everyone to understand the risks associated with zero-day vulnerability and take proactive steps to guard against them. With Vi, you have more than just a telecom partner; you have a digital ally, offering secure international roaming, fast data, and reliable communication so that you never have to compromise safety for convenience.

Curious minds never stop scrolling! If you enjoyed this read—check out how to deactivate voicemail like a pro,, how to track your mobile phone with the imei tracker, mastering how to hide apps in your phone, and if you’ve ever wondered what is an antivirus —we’ve got the lowdown on that too !

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