27.08.25

Zero-click Attacks – What are They

Understanding and Preventing Zero-Click Attacks

Many types of cyber-attacks involve manipulating users into doing certain tasks – whether it’s sharing login credentials, downloading dangerous attachments or clicking on harmful links – to help hackers compromise their systems or data. However, some incidents can be launched without these exchanges. In particular, zero-click attacks entail hackers leveraging software flaws in users’ devices or applications to deploy malicious code (e.g. viruses, worms, spyware or ransomware), all without the need for any communication or activity from the users. Also known as zero-click exploits, these incidents require cyber-criminals to deviate from typical attack patterns and utilise more stealthy techniques to quietly infiltrate users’ technology.

Such characteristics also make these attacks difficult to detect, often prompting prolonged and destructive incidents that generate serious consequences for affected users. As cyber-incidents continue to become more sophisticated in nature, zero-click attacks are on the rise, ultimately representing a new frontier in security threats for organisations across industry lines. With this in mind, it’s critical for organisations to better understand these exploits and how to prevent them. This article provides more information on zero-click attacks, outlines how they can impact organisations and highlights related mitigation tips. 

Zero-clicks Attacks Explained

Unlike phishing scams and other social engineering tactics, zero-click attacks don’t rely on interactions between cyber- criminals and users to be successful. Rather, these incidents involve skilled hackers exploiting software vulnerabilities in users’ devices (e.g. tablets, smartphones, laptops and desktop computers) or applications. Such exploitation typically stems from cyber-criminals delivering specifically crafted data packets to unprotected systems and services without users’ knowledge. Common targets for zero-click exploits include poorly secured Internet of Things (IoT) devices and mobile applications, particularly those with email, instant messaging, video-conferencing and voice-calling features. These applications frequently receive and analyse files from a range of external sources, making them vulnerable due to their ability to automatically process such content in different ways (e.g. generating previews of messages or media before users open them). What’s more, these applications often have end-to-end encryption capabilities, meaning that the content of data packets sent through them remains unknown to all parties except the sender and receiver. Such capabilities can make it harder to identify attacks. Because they leave little to no trace, zero-click exploits can go uncovered for extended periods, allowing cyber-criminals to cause lasting damage to impacted users’ systems and data. Complicating matters, hackers usually implement advanced strategies to install and delete these exploits, removing any evidence that they even took place. This can significantly hinder incident investigation and remediation efforts.

How Zero-clicks Attacks Impact Organisations

Zero-click attacks can affect organisations in many ways, leading to the following ramifications:

• Stolen funds and assets – Through these attacks, cyber-criminals can gain unauthorised access to confidential business records, private stakeholder information and intellectual property. This could enable hackers to commit corporate espionage and steal critical funds and assets, leaving organisations with considerable financial and reputational losses.
• Damaged systems and technology – Such exploits may also allow cyber-criminals to leverage compromised devices to move laterally across corporate networks, escalate their privileges and infiltrate organisations’ larger IT infrastructures, ultimately paving the way for more widespread damage and operational disruptions. As the number of remote workers and IoT devices continues to rise, these trends could expand possible attack surfaces for zero-click exploits, compounding related losses and creating opportunities for future incidents.
• Regulatory and legal penalties – When these attacks impact sensitive stakeholder information, organisations could be held liable for failing to properly protect such data. This may lead to costly legal action and reputational damage. Furthermore, organisations could face substantial regulatory penalties for breaching applicable data privacy laws.

Risk Mitigation Strategies

There are various risk management measures organisations can implement to help lower the likelihood of zero-click attacks and limit associated losses if these incidents do happen. Here are some mitigation strategies to consider:

• Maintain updated software. Organisations should make it a priority to regularly update all workplace devices, operating systems, applications and firmware to help patch known vulnerabilities and other security weaknesses, thereby blocking cyber-criminals from exploiting this technology. Enabling automatic software updates and using patch management tools can simplify this process.
• Utilise multilayered security solutions. By equipping their devices with advanced threat identification systems, antivirus programs, firewalls and intrusion detection tools, organisations can ensure greater visibility of their entire IT infrastructures and watch for any abnormal activity. Such solutions can help stop cyber- criminals in their tracks, addressing attacks before they cause more severe damage. Organisations should also consider using artificial intelligence and machine learning tools to monitor software patterns and swiftly identify suspicious anomalies that may indicate zero-click exploits.
• Establish segmented networks and access controls. To prevent cyber- criminals from travelling laterally through their systems amid zero-click exploits and expanding attack surfaces, organisations should segment their networks. This way, hackers will only be able to compromise a small portion of corporate resources at a time, minimising the risk of large-scale damage and disruptions. In addition, organisations should enforce strict access controls and uphold the principle of least privilege, only allowing employees to handle systems and data deemed necessary for their roles.
• Promote proper cyber-hygiene. Although zero-click attacks don’t stem from interactions between hackers and users, it’s still important for organisations to educate their employees on this threat and encourage solid cyber-hygiene through routine awareness training. Key topics to address include creating strong passwords, recognising and reporting unusual network activity, and periodically reviewing and removing unnecessary applications.
• Vet all vendors and applications. Organisations should carefully evaluate all third-party software vendors and applications, especially niche or lesser-known providers, for possible security flaws before finalising their contracts and purchases. In doing so, organisations can avoid introducing new vulnerabilities and offering further avenues for zero-click exploits.
• Have a plan. Creating cyber-incident response plans can help organisations ensure necessary procedures are taken when attacks occur, keeping related losses at a minimum. These plans should be well documented, practised on a regular basis and address a range of cyber-attack scenarios (including zero-click exploits).

Conclusion

Zero-click attacks present numerous risks for organisations of all sizes and sectors. As these attacks become increasingly prevalent, it’s vital for businesses to have proper safeguards in place. By maintaining awareness of zero-click exploits and taking sufficient steps to address them, organisations will be better equipped to navigate this evolving cyber-security landscape and, in turn, prevent major losses.

Contact us today for more information and cyber-risk-management guidance

Information provided by Zywave with a contribution from Lisa Langley, Cert CII, Team Leader Professional Risks, Cox Mahon Ltd.