Be Prepared for DDoS Attacks! Understand the Threats, Risks, and Countermeasures Correctly

In today’s world, where the internet has become indispensable to our lives, the threat of cyber attacks is increasing daily.

Among these, one particularly noteworthy attack method is the “DDoS attack.”

This article explains what a DDoS attack is, its types, aims, and the nature of the damage it can cause.

Furthermore, it introduces specific countermeasures to protect your important systems from DDoS attacks.

DDoS Attacks
1. Main Methods of DDoS Attacks
2. Difference Between DDoS Attacks and DoS Attacks
3. Aims of DDoS Attacks
Damage Caused by DDoS Attacks
1. Service Interruption
2. Financial Damage
3. Decline in Social Credibility
4. Becoming a Stepping Stone
Countermeasures Against DDoS Attacks
1. Strengthening Network Settings
2. Using DDoS Mitigation Tools
3. Using DDoS Mitigation Services Provided by Cloud Providers
4. Preventing Malware Infection

1. What is a DDoS Attack?

A DDoS attack (Distributed Denial of Service attack) is a cyber attack that stops services by sending massive amount of unauthorized data from multiple computers to a target website or server.

1-1. Main Methods of DDoS Attacks

DDoS attacks can be broadly classified into the following three types, depending on the method used.

Each method has its own characteristics, and attackers may use them differently depending on the target’s vulnerabilities.

① Volume-Based Attacks

Volume-based attacks are the most common form of DDoS attacks.

The main purpose of this attack is to saturate the target’s network bandwidth or server resources.

Specifically, the following methods can be used:

・UDP (User Datagram Protocol) Flood

: Sends a large number of UDP packets to consume the target’s resources.

・ICMP (Internet Control Message Protocol) Flood

: Abuses the ping command to send a large number of ICMP echo requests.

・Reflection Attack

: Abuses protocols such as DNS and NTP to generate a large number of responses with small requests.

② Protocol Attacks

Protocol attacks exploit the characteristics and vulnerabilities of network protocols to exhaust the target’s system resources.

Attackers use the following methods, for example:

・SYN Flood: Exploits the TCP connection establishment process to send a large number of incomplete connection requests.

・Slowloris: Continues to send HTTP requests partially, occupying the server’s connection for a long time.

③ Application Layer Attacks

Application layer attacks are more sophisticated and difficult-to-detect attacks that target application-level vulnerabilities such as web servers.

A typical method is HTTP GET/POST flood, which sends a large number of legitimate HTTP requests to overload the web server.

These attack methods may be used alone or in combination with multiple methods.

In addition, attack techniques are constantly evolving, and new methods and variations of existing methods are constantly emerging.

1-2. Difference Between DDoS Attacks and DoS Attacks

DDoS attacks use multiple attack sources (often botnets), while DoS attacks (Denial of Service attacks) are performed from a single attack source.

Both DDoS attacks and DoS attacks are cyber attacks that aim to stop services, but DDoS attacks are carried out simultaneously from multiple computers. Therefore, DDoS attacks are overwhelmingly larger in scale.

In addition, DDoS attacks often cause more serious damage and are more difficult to counter.

1-3. Aims of DDoS Attacks

The aims of DDoS attacks are mainly the following three:

・Financial Demands

: The attacker demands money from the target and threatens to stop the attack.

・Service Disruption

: Aims to disrupt the services of rival companies, causing business disruption and damaging their reputation.

・Political Intentions

: Attacks government agencies and critical infrastructure to assert political messages or as part of protest activities.

2. Damage Caused by DDoS Attacks

DDoS attacks can have serious and significant impacts on businesses.

The damage ranges from temporary to long-term, affecting not only economic losses but also the company’s reputation and competitiveness.

2-1. Service Interruption

The most direct impact is that the targeted service or website becomes unavailable.

DDoS attacks overload servers and networks, preventing legitimate users from accessing services.

This can lead to decreased customer satisfaction, business interruptions, and even shutdowns.

2-2. Financial Damage

The financial damage caused by DDoS attacks is very diverse.

For example, the following losses can be cited:

・Sales Decline: Direct loss of sales due to the shutdown of online services and e-commerce sites.

・Opportunity Loss: Loss of potential customers and transactions.

・Recovery Costs: Costs associated with system recovery and security reinforcement after an attack.

In addition to the above, there are cases where companies are sued due to the decline in brand image or leakage of customer information caused by DDoS attacks, which can result in even greater costs.

2-3. Decline in Social Credibility

DDoS attacks can also have a significant impact on a company’s social credibility.

For example, if it is announced that a company has been subjected to a DDoS attack, it may be judged that the company’s security measures are insufficient, which may lead to a decline in brand image. In addition, if services are suspended due to a DDoS attack, customers and business partners may recognize the company as “untrustworthy”, which may lead to a decline in reputation.

In the case of listed companies, damage from DDoS attacks may also lead to a decline in stock prices.

2-4. Becoming a Stepping Stone

Some DDoS attacks are used as stepping stones for other attacks.

Once an attacker successfully carries out a DDoS attack and takes control of a server, they may use that server to attack other systems.

This can lead to the spread of damage to other companies.

In this way, the damage caused by DDoS attacks not only causes financial losses and business interruptions, but also causes significant damage to the company’s credibility and reputation. To minimize these risks, proactive measures and rapid responses are essential.

3. Countermeasures Against DDoS Attacks

DDoS attacks are evolving in method and scale every day, making it difficult to defend against them with a single measure alone.

Therefore, it is important to build a multi-layered and comprehensive defense strategy. The main DDoS countermeasures are explained in detail below.

3-1. Strengthening Network Settings

Properly configuring network settings is a basic defense against DDoS attacks.

Let’s strengthen the network while paying attention to the following points.

・Proper Firewall Settings

The firewall plays an important role in monitoring traffic flowing into the network and blocking unauthorized access.

Proper settings can prevent some DDoS attacks in advance.

・Closing Unnecessary Ports

Closing unnecessary ports on the network can reduce the routes available to attackers.

In particular, it is important to close ports that are not in use or that pose a security risk, and to open only the minimum necessary ports.

・Implementing Traffic Filtering

By implementing traffic filtering, it is possible to identify and block malicious traffic based on specific patterns or protocols.

This can reduce traffic from attackers.

3-2. Using DDoS Mitigation Tools

By introducing specialized DDoS mitigation tools, you can process large amounts of traffic while detecting and blocking anomalies.

The tools can be provided on-premises or in the cloud, and are characterized by real-time monitoring, automatic defense, and pattern analysis functions.

・Real-Time Monitoring

Monitors network traffic in real time and detects abnormal traffic patterns.

This makes it possible to detect attacks early.

・Automatic Defense

This is a function that automatically takes defensive measures when abnormal traffic is detected.

For example, it is possible to automatically block the IP address of the attack source or send real-time notifications to the administrator.

・Pattern Analysis

It is possible to analyze the nature and pattern of attacks based on detailed attack reports.

This can lead to strengthening measures against future attacks.

3-3. Using DDoS Mitigation Services Provided by Cloud Providers

Major cloud providers offer DDoS mitigation services such as the following:

・Amazon Web Services (AWS) Shield

・Google Cloud Armor

・Microsoft Azure DDoS Protection

By using these services, you can achieve effective protection without specialized knowledge or expensive equipment investment.

The main benefits of cloud DDoS mitigation services are as follows:

・Usable Without Specialized Knowledge

: Cloud providers handle DDoS attack monitoring and mitigation, so you can use it with peace of mind even without specialized knowledge.

・Scalability

: You can flexibly expand your defense capabilities according to the scale of the attack.

・Cost Performance

: You can reduce costs compared to on-premises DDoS mitigation solutions.

3-4. Preventing Malware Infection

Attackers build large-scale botnets by infecting vulnerable PCs with malware.

It is important to prevent malware infection on your company’s PCs and devices in order to significantly reduce the risk of being botnetized.

In addition, malware infection can cause various secondary damages other than DDoS attacks, such as information leakage and ransomware damage.

It is important for companies to thoroughly implement basic security measures to prevent malware infection.

Summary

DDoS attacks are a serious threat to businesses and organizations.

The impact is not limited to service interruptions, but extends to financial losses and a decline in social credibility.

By taking appropriate measures, you can reduce the risk of attack and minimize damage.

Constantly keeping abreast of the latest threat trends and continuously reviewing security measures is the key to maintaining a safe business.