
Announcement Template
12월 14, 2023What is Zero-Day? Definition, Risks, Examples, Prevention

1. What is Zero-Day (0-day)?
Zero-day attacks stand out as one of the most disruptive cybersecurity threats, posing a significant challenge even to security experts. ‘Zero-day’ refers to an attack that occurs on ‘day-zero’, which is before a security vulnerability is publicly disclosed. Attackers discover and exploit these vulnerabilities while they remain unknown to software developers and security professionals. The essence of a zero-day attack lies in its unpredictability and the difficulty of defense. Attackers use these vulnerabilities to deploy malware. Although there are various types of attacks such as ransomware, backdoor installations, network interference, and DDoS attacks, malware utilizing zero-day attacks remain among the most active.
For an in-depth definition of Zero-Day Attack, please refer to the ITU-T X.1236 established by International Telecommunication Union (ITU).
6.1. General characteristics, section 6.1.1. Zero-day malware attacks
Targeted email attacks mainly includes malware that are hard to detect with traditional pattern recognition. Malware exploiting zero-day vulnerability can spread before organizations effectively prevent the threat. For example, malicious developers can create zero-day malware with vulnerability of security program, before the security program is deployed.
2. Risks of Zero-Day
Hard to predict
Zero-day attacks are challenging to prevent or prepare in advance, as they occur when vulnerabilities have not been disclosed. The lack of prior knowledge about these vulnerabilities make it hard to predict when and how an attack will occur.
This distinctive feature is elaborated in the definition of 7.1.1. Zero-day malware in ITU-T X.1236.
7.1.1. Zero-day malware
It is challenging for security systems to identify the zero-day malware, as it is not identified or registered in large-scale databases.
Severe Consequences
Zero-day attacks can result as identity theft, financial data leakage and system shutdown. These could lead to further substantial losses of companies.
The general types of damage caused by these attacks are detailed in Section 7.1.1 of the ITU-T X.1236 on zero-day malware.
7.1.1. Zero-day malware
Attackers insert attachments or links with unidentified malware into emails to exploit zero-day vulnerability. They additionally craft emails to induce users into downloading attachments or clicking links.
Zero-day malwares can damage or delete files and programs by gaining access to the victim’s computer memory.
Delayed Response
It takes time for security companies to develop and distribute patches because zero-day vulnerabilities are unidentified beforehand. Damages broaden as patch distribution is delayed.
Difficulty in Recovery
Delay in finding a solution to a zero-day attack also makes it challenging to recover the system to its original state. This delay and a lack of information complicate recovery or restoration efforts.
3. Types of Attackers
Zero-day malware attacks are carried out by attackers with a variety of motivations. Gaining an understanding of their motives, targets, and the techniques they use is crucial for the development of effective cybersecurity strategies.
Hacktivists
Hacktivists conduct attacks to convey social or political messages by drawing public attention to their causes. Their objectives range from information disclosure to exposing the illegal activities of governments or large enterprises.
Cybercriminals
Cybercriminals exploit zero-day vulnerabilities to steal personal financial information, company credentials, or other valuable information for their own gain.
Corporate Spies
Corporate spies engage in high-level, targeted attacks to uncover the secrets of competitors. Their goal is to gain competitive advantages or acquire any important market information.
Cyber Warfare
Cyber warfare is conducted by nations or political actors with the objective of gathering information, disrupting infrastructure, or exerting political influence through attacks on or monitoring of a target country’s cyberinfrastructure.
4. Examples of Zero-Day Attacks
Attack on Iran's Nuclear Facilities —Stuxnet
One of the most notable instances of a zero-day vulnerability exploitation is the ‘Stuxnet attack on Iran’s nuclear facilities’.
Stuxnet, discovered in 2010, was a highly sophisticated malware specifically designed to target Iran’s Natanz nuclear facility. Its primary purpose was to disrupt Iran’s uranium enrichment program. Stuxnet infiltrated the industrial control systems managing Iran’s centrifuges, resulting in physical damage. The malware exploited several zero-day vulnerabilities in the Windows operating system and notably spread through USB drives.
What set Stuxnet apart was its unique objective. Instead of focusing solely on data corruption or system paralysis, Stuxnet aimed to manipulate specific industrial control systems, leading to tangible and physical destruction. This case demonstrated how cyber actions have tangible and physical consequences, showcasing the evolving landscape of cyber threats and their impact on the physical realm.
Attack on Microsoft Word Users
5. Zero Day Protection and Prevention
With the rapid growth of the internet driving the expansion of the IT industry, security technologies are developing with significant progress. Nevertheless, we are still not free from zero-day attacks.
To minimize the damage, the following methods can be helpful:
Regular Updates
Regular updates ensure users that systems and software are up-to-date and security patches are promptly applied.
Network Firewalls
Implementing network firewalls blocks malicious traffic and prevents external intrusions.
Intranet Security
Reinforcing internal network security prevents internal attacks and helps fortify against zero-day attacks.
Security Applications
Enhancing application security and introducing security solutions improve detecting and blocking malicious elements.
User Education
Employee and user cybersecurity training helps avoid malicious links and encourages reporting suspicious activities.
Malicious File Detection
Utilize antivirus and malware detection solutions to identify and block malicious files.
Network Monitoring
Continuously monitor network activity 24/7, detect unusual signs, and respond swiftly.
6. Solutions
The response to zero-day attacks must be multifaceted. The most crucial elements in preventing and responding to these attacks are appropriate preventive measures and a rapid response strategy.
First, both organizations and individuals should recognize cybersecurity as an essential element. Regular security updates, strong password policies, and data backups are basic yet essential measures.
In the event of detecting a zero-day attack, it’s crucial to immediately disconnect the device from all network connections without turning it off. This prevents further damage and aids in preserving data for forensic investigation.
Reset all system and administrator account passwords, and if necessary, disable Wi-Fi and deactivate critical network connections.
If there is no decryption solution for the infected system, consider attempting system restoration or reinstalling the OS, which is the most reliable way to cleanse and recover the infected system. Installing and updating antivirus software, along with regular scans, are essential to remove any residual infections and prevent future attacks.
7. References
ITU-T X.1236
How to Prevent Zero-Day Attacks in 5 Steps
https://cybriant.com/how-to-prevent-zero-day-attacks-in-5-steps/
Impact of zero-day attacks on a company’s productivity
https://cloudkul.com/blog/impact-of-zero-day-attacks-on-a-companys-productivity/
What is a zero-day exploit? Definition and prevention tips
https://us.norton.com/blog/emerging-threats/zero-day-exploit
What Is a Zero-Day Attack?
https://www.akamai.com/glossary/what-is-zero-day-attack
What is a Zero-day Attack? – Definition and Explanation
https://www.kaspersky.com/resource-center/definitions/zero-day-exploit
Explanation Of The Zero-Day Attack
https://www.wallarm.com/what/explanation-of-the-zero-day-attack