The cyber defenders are at a loss of words as the cybercriminals are focusing on zero-day attack tactics.
The term “zero-day” refers to the fact that the vendor or developer has only just learned of the flaw – which means they have “zero days” to fix it. A zero-day attack takes place when hackers exploit the flaw before developers have a chance to address it.
Zero-day is sometimes written as 0-day. The words vulnerability, exploit, and attack are typically used alongside zero-day, and it’s helpful to understand the difference. A zero-day vulnerability is a software vulnerability discovered by attackers before the vendor has become aware of it.
Because the vendors are unaware, no patch exists for zero-day vulnerabilities, making attacks likely to succeed. Software often has security vulnerabilities that hackers can exploit to cause havoc. Software developers are always looking out for vulnerabilities to “patch” – that is, develop a solution that they release in a new update.
However, sometimes hackers or malicious actors spot the vulnerability before the software developers do. While the vulnerability is still open, attackers can write and implement code to take advantage of it. This is known as exploit code. The exploit code may lead to the software users being victimized – for example, through identity theft or other forms of cybercrime.
Once attackers identify a zero-day vulnerability, they need a way of reaching the vulnerable system. They often do this through a socially engineered email – i.e., an email or other message that is supposedly from a known or legitimate correspondent but is actually from an attacker. The message tries to convince a user to perform an action like opening a file or visiting a malicious website.
Doing so, it downloads the attacker’s malware, which infiltrates the user’s files and steals confidential data. When a vulnerability becomes known, the developers try to patch it to stop the attack. However, security vulnerabilities are often not discovered straight away. It can sometimes take days, weeks, or even months before developers identify the vulnerability that led to the attack.
And even once a zero-day patch is released, not all users are quick to implement it. In recent years, hackers have been faster at exploiting vulnerabilities soon after discovery. Exploits can be sold on the dark web for large sums of money. Once an exploit is discovered and patched, it’s no longer referred to as a zero-day threat.
Zero-day attacks are especially dangerous because the only people who know about them are the attackers themselves. Once they have infiltrated a network, cybercriminals can either attack immediately or sit and wait for the most advantageous time to do so. Targeted zero-day attacks are carried out against potentially valuable targets – such as large organizations, government agencies, or high-profile individuals.
Non-targeted zero-day attacks are typically waged against users of vulnerable systems, such as operating systems or browsers. Even when attackers are not targeting specific individuals, large numbers of people can still be affected by zero-day attacks, usually as collateral damage. Non-targeted attacks aim to capture as many users as possible, meaning that the average user’s data could be affected.
Because zero-day vulnerabilities can take multiple forms – such as missing data encryption, missing authorizations, broken algorithms, bugs, problems with password security, and so on – they can be challenging to detect. Due to the nature of these types of vulnerabilities, detailed information about zero-day exploits is available only after the exploit is identified.
Organizations that are attacked by a zero-day exploit might see unexpected traffic or suspicious scanning activity originating from a client or service. Some of the zero-day detection techniques include: Using existing databases of malware and how they behave as a reference. Although these databases are updated very quickly and can be useful as a reference point, by definition, zero-day exploits are new and unknown.
So, there’s a limit to how much an existing database can tell you. Alternatively, some techniques look for zero-day malware characteristics based on how they interact with the target system. Rather than examining the code of incoming files, this technique looks at the interactions they have with existing software and tries to determine if they result from malicious actions.
Increasingly, machine learning is used to detect data from previously recorded exploits to establish a baseline for safe system behavior based on data from past and current interactions with the system. The more data is available, the more reliable detection becomes.
Disclaimer: The information provided in this article is solely the author’s opinion and not investment advice – it is provided for educational purposes only. By using this, you agree that the information does not constitute any investment or financial instructions. Do conduct your own research and reach out to financial advisors before making any investment decisions.