Redazione RHC : 29 July 2025 07:15
In recent years, cybersecurity has seen the emergence of increasingly sophisticated threats, capable of compromising devices and personal data without the user taking any action. Among these, so-called zero-click exploits represent one of the most insidious and difficult-to-detect forms of attack. These exploits allow hackers to take control of a device simply by sending a message or interacting with the system in ways invisible to the user.
Unlike traditional attacks, which require some type of interaction—such as clicking a link or opening an attachment—zero-click exploits exploit hidden vulnerabilities within software or communication protocols. This means that even without any awareness or action on the victim’s part, malware or spyware can be installed and activated, with potentially serious consequences for privacy and security.
In this article, we’ll analyze how these invisible attacks work, the devices most at risk, and what protection strategies to adopt to effectively defend against them. Understanding how zero-click exploits work is the first step to securing your data in an increasingly connected and vulnerable world.
A zero-click exploit is a type of cyber attack that requires no action from the victim to compromise a device. Unlike traditional phishing or malware attacks, where the user must click a link or open a file, in this case, all that’s needed is for the device to receive a specially crafted message or communication to activate the vulnerability.
These exploits exploit security flaws in system software, messaging apps, or communication protocols. For example, a text message or VoIP call can hide malicious code that executes automatically. This makes zero-click exploits extremely dangerous, because they are invisible and difficult to detect by antivirus or traditional protection systems.
To better understand what software vulnerabilities are and how exploits work, you can learn more about software vulnerabilities by visiting resources like the National Vulnerability Database (NVD) or reading security reports from companies like Google Project Zero. The growing sophistication of zero-click exploits makes them a real threat to mobile devices, computers, and even IoT devices.
Zero-click exploits exploit complex technical vulnerabilities in operating systems and applications. These attacks rely on the automatic execution of malicious code as soon as the device receives specific input, without the user having to interact.
A common mechanism is the use of buffer overflows, where malicious code exceeds the intended memory capacity, allowing the attacker to execute arbitrary commands. Other methods include injecting code into messaging protocols like SMS, iMessage, or WhatsApp, which don’t require opening the message to trigger the exploit.
The most common attack vectors are text messages, VoIP calls, and push notifications. For example, an exploit could be triggered simply by receiving a call that exploits a flaw in the SIP protocol, or an encrypted message containing hidden code in the payload. These attacks can completely compromise the device, giving access to personal data, microphone, camera, and much more.
One of the most famous examples of zero-click exploits is the spyware Pegasus, developed by the Israeli company NSO Group. Pegasus exploited zero-click vulnerabilities to infiltrate the smartphones of activists, journalists, and politicians without them taking any action. The attack was carried out simply through messages or calls, making it very difficult to detect.
Zero-day vulnerabilities are security flaws that are still unknown to manufacturers and unpatched. These flaws are often discovered and exploited through zero-click exploits. A recent example was the bug discovered in iMessage that allowed the remote installation of spyware simply by receiving a message. Apple promptly released a patch to fix the issue, but in the meantime, many devices were vulnerable.
Other known cases include zero-click exploits against WhatsApp, where a call could infect a device even if it wasn’t responding. In 2019, this vulnerability prompted WhatsApp to urgently issue an update to stop highly sophisticated spyware attacks.
These examples highlight how zero-click exploits aren’t just theories, but real, active threats affecting millions of devices worldwide. Attackers exploit these techniques to spy, steal data, or take complete control of smartphones and computers without leaving any obvious traces.
Finally, the difficulty of detecting these attacks makes them particularly dangerous. Victims often don’t notice anything until it’s too late.
Zero-click exploitsrepresent one of the most complex cybersecurity challenges. Their difficulty to defend stems primarily from the fact that they require no action or interaction from the user. Without a click, a file opening, or consent, traditional protection systems based on user behavior are ineffective.
Another reason is that these exploits exploit often unknown vulnerabilities, called zero-days, for which there are no immediate patches or updates. Hackers can exploit these vulnerabilities before software vendors have time to intervene, leaving devices and systems exposed for varying lengths of time.
Furthermore, zero-click exploits use highly sophisticated methods to hide themselves. The malicious code is often embedded in encrypted messages or communications, making it difficult for antivirus or traditional security tools to analyze them. This “invisibility” allows attackers to operate undetected and target specific victims.
The technical complexity of these attacks requires advanced defense solutions, such as AI-based detection systems and continuous monitoring of device behavior. However, even these technologies do not guarantee complete protection, especially if the vulnerabilities are unknown or newly discovered.
Finally, the rapidity with which new zero-click exploits are developed and deployed makes it difficult for security companies and users to keep pace. Prevention, therefore, also involves constantly updating devices, carefully configuring applications, and maintaining a high level of awareness of emerging threats.
Zero-click zero-day exploits are not just tools used by hackers, but actual goods traded in an underground market with extremely high values. Companies like Zerodium have built a business on buying and selling unknown vulnerabilities, offering rewards of up to millions of dollars for a single working exploit.
These exploits are so high because they exploit unknown and difficult-to-detect flaws. For example, Zerodium has offered prices exceeding $1 million for zero-click vulnerabilities on operating systems like iOS and Android, considered the most valuable because they allow a device to be compromised without any user interaction.
These exploits aren’t just used by cybercriminals. They often end up in the hands of companies that develop sophisticated spyware, like NSO Group, which develop surveillance systems that end up in the hands of governments seeking to surveil people deemed “of interest.” It’s a legal market in some countries, but ethically controversial because it allows espionage activities that can violate fundamental rights.
The value of zero-click, zero-day exploits also stems from a deeper reason: information is power. Anyone possessing such an exploit can access confidential data, private conversations, and industrial secrets. In an era where privacy and data security are increasingly central, this possibility becomes invaluable.
At the root of it all is a delicate balance between security research, economic interest, and civil rights risks. As long as there is a market willing to pay this much for these vulnerabilities, zero-click, zero-day exploits will continue to be developed, sold, and used, fueling a never-ending race between attackers and defenders.
The growing prevalence of zero-click exploits requires a radical shift in the way we approach cybersecurity. The traditional model, based primarily on reacting to attacks, is no longer sufficient. We need a proactive strategy that anticipates threats before they can strike. But the question is: how can we anticipate an unknown threat?
Technologies based on artificial intelligence and machine learning are becoming increasingly central to defending against invisible attacks like zero-click exploits. These systems continuously analyze the behavior of devices and networks, identifying suspicious anomalies even in the absence of obvious signs of an attack.
Another key element is the collaboration between security companies, governments, and software developers. Timely sharing of vulnerability and exploit information allows for faster and more effective countermeasures, reducing the time devices remain exposed.
User education also remains a key pillar, even though zero-click exploits don’t require direct action from victims. Being aware of threats, keeping devices updated, and adopting good security practices help minimize overall risks.
Finally, the future of cybersecurity will require an integrated approach, combining advanced technologies, rigorous security policies, and a widespread security culture. Only in this way will it be possible to effectively protect data, devices, and privacy in an increasingly connected and vulnerable world.
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