Zero Day Exploit

What is a Zero-Day Vulnerability?

A zero-day (also known as 0-day) vulnerability is a vulnerability that’s unknown to the vendor and hasn’t yet been patched.

The term zero-day refers to the number of days that the vendor has had to patch the issue since it was initially discovered.

The term actually encompasses three different concepts: vulnerabilities, exploits, and attacks.

Zero-Day Exploit

A zero-day exploit is the technique used to leverage a zero-day vulnerability.

Exploits can be in the form of malicious software (malware), code, or scripts that leverage the unpatched vulnerability to compromise systems.

These exploits are highly valuable since they can bypass security defenses, which have not been updated to protect against the new threat.

Zero-Day Attack

A zero-day attack is when threat actors use a zero-day exploit to either gain access to a system, steal data, or cause other forms of damage.

Since the vulnerability is unknown to the vendor, and no patch exists, zero-day attacks can be highly effective and difficult to prevent.

Threat actors often use these attacks to target high-value systems like government or corporate networks.

How do zero-day attacks work?

While each zero-day is unique, most attacks follow a similar sequence of events. These are as follows:

Discovery: An attacker discovers a vulnerability in a piece of software or system that the vendor is unaware of.
Research: The attacker researches the vulnerability to understand the extent of the issue and how it can be exploited.
Creation: The attacker creates an exploit, which is a piece of malicious code that leverages the vulnerability to escalate privileges, execute malicious commands, or gain unauthorized access to sensitive data.
Testing: The exploit is tested to ensure it wont trip any of the target’s security defenses, for example antivirus software.
Delivery Mechanism: The attacker chooses a method to deliver the exploit to the target. This is often done via phishing emails, malicious websites, infected software downloads, or social engineering.
Infiltration: The exploit is executed on the target system, either automatically or through user interaction, such as clicking a malicious link.
Payload Delivery: Once successfully executed, the exploit may install additional malware, create backdoors, or execute commands.
Outcome: The attacker gains unauthorized access, escalates privileges, steals data, or otherwise disrupts system operations.

Examples of zero-day attacks

Stuxnet (2010): Stuxnet targeted Iranian nuclear facilities, specifically aiming to disrupt uranium enrichment processes. It exploited multiple zero-day vulnerabilities in Windows, allowing it to spread and operate undetected. The worm was able to alter the speed of centrifuges, causing physical damage to the nuclear equipment.
Heartbleed (2014): Heartbleed was a software vulnerability in the OpenSSL cryptographic library. OpenSSL is widely used to secure internet traffic. Exploiting this vulnerability allowed attackers to read the memory of affected systems, potentially exposing sensitive data like passwords and encryption keys. The widespread use of OpenSSL meant that millions of servers and devices were vulnerable.
EternalBlue (2017): EternalBlue was a zero-day exploit that targeted a vulnerability in Microsoft’s SMB (Server Message Block) protocol. It was developed by the NSA and later leaked by the hacking group Shadow Brokers. This exploit was notably used in the WannaCry ransomware attack, which affected hundreds of thousands of computers worldwide. The attack caused significant disruption, particularly to healthcare systems in the UK.

Who Carries out Zero-Day Attacks?

Nation-State Actors: Government-sponsored groups conducting cyber operations for strategic, political, or economic purposes.
Cybercriminals: Individuals or organized crime groups looking for financial gain.
Hacktivists: Activists using hacking to promote political or social causes.
Insiders: Disgruntled Employees or contractors exploiting vulnerabilities within their organization.

Who are Targets for Zero-Day Exploits?

Government Agencies: To steal sensitive information or disrupt operations.
Large Corporations: To access valuable data, such as intellectual property, customer information, or financial records.
Critical Infrastructure: Including power grids, water supplies, and transportation systems, to cause widespread disruption.
Healthcare Systems: To obtain personal health information or disrupt medical services.
Financial Institutions: To access banking information, conduct fraud, or disrupt financial operations.
Individual Users: To steal personal information, financial details, or use their devices for further attacks.
Educational Institutions: To access research data, personal information of students and staff, or disrupt academic operations.

How to identify zero-day attacks

Identifying zero-day attacks are challenging due to their unknown nature. However, there are a couple of strategies that may help:

Behavioral Analysis: Monitor for unusual behavior in network traffic, user activity, and system processes that deviate from the norm.
Indicators of Compromise (IOCs): Look for signs such as unusual outbound traffic, unexpected system changes, or anomalies in user behavior.
IDS / IPS: Use Intrusion Detection and Prevention Systems to identify and block suspicious traffic in real-time.
Endpoint Detection and Response (EDR): Setup EDR tools to continuously monitor and respond to potential threats on endpoints.
Threat Intelligence Feeds: Subscribe to threat intel feeds that provide information on emerging threats, vulnerabilities, and leaked employee and vendor credentials.
Vulnerability Scanners: Use automated tools to regularly scan your network and applications for known vulnerabilities.
Penetration Testing: Conduct regular penetration tests to identify vulnerabilities before they’re exploited.
Anomaly Detection: Implement AI-based anomaly detection tools that can recognize new threats.
SIEM Solutions: Implement a SIEM (Security Information and Event Management) to collect and analyze log data from various sources to detect unusual patterns..
Honeypots: Deploy decoy systems to attract attackers and study their techniques.
Sandboxes: Use sandboxing to execute and analyze suspicious files in an isolated environment.
Patch Regularly: Ensure that all systems are updated regularly to prevent known vulnerabilities being exploited.
Patch Testing: Test software updates in a controlled environment before deploying them to ensure they don’t introduce new vulnerabilities.