What Is a Bot Attack?
A bot attack involves the use of automated software programs to perform tasks that can be malicious, aiming to exploit the integrity of websites, applications, or networks. Bots can mimic human behavior and operate at a scale that makes detection difficult without sophisticated defenses.
During an attack, bots might overwhelm a system with requests, leading to service outages or unauthorized access to data. Bot attacks can significantly disrupt and harm business operations. These often exploit vulnerabilities in security systems to steal data, manipulate analytics, or overload systems and applications.
Bot attacks can be used for a range of malicious objectives, from distributed denial of service (DDoS), to account takeovers and data scraping. Malicious bots, in the hands of threat actors, can cause significant harm and require strong countermeasures.
This is part of a series of articles about bot protection.
In this article:
Financial Costs and Losses
A malicious bot attack can cause financial losses through direct and indirect means. Distributed denial-of-service (DDoS) attacks can disrupt online services, leading to lost revenue and compensation costs for downtime.
Bots engaging in click fraud can drain advertising budgets by generating fake interactions. Additionally, fraudulent transactions caused by bot-driven credential stuffing or carding attacks may result in chargebacks, legal fees, and regulatory fines. Organizations also face increased cybersecurity spending to recover from attacks and implement stronger defenses.
Data Security Breaches and Compliance Risks
Botnet attacks are often used to exfiltrate sensitive data, including customer records, login credentials, and proprietary business information. Automated bots can exploit software vulnerabilities, scrape protected content, or use credential stuffing techniques to gain unauthorized access.
Once inside, attackers may sell or publicly expose stolen data, leading to regulatory penalties, loss of customer trust, and compliance violations under data protection laws like GDPR or CCPA.
Reputational Damage and Trust Loss
A successful bot attack can severely damage a company's reputation. When customer data is compromised, or services are repeatedly disrupted, users may lose confidence in the organization’s ability to protect their information.
Negative media coverage and social media backlash can amplify the damage, discouraging potential customers and business partners from engaging with the company. Long-term effects include decreased brand loyalty, lower customer retention rates, and increased public scrutiny.
Operational Disruption
Bot attacks can interfere with normal business operations by overwhelming IT infrastructure and consuming critical resources. A high volume of automated traffic, known as a denial of service (DoS) or distributed denial of service (DDoS) attack, can degrade website performance or even cause downtime. Such attacks make it difficult for legitimate users to access services, and lead to lost sales and missed business opportunities.
Bots targeting APIs can overload backend systems, delaying order processing and customer support functions. In severe cases, prolonged disruption can halt business activities, leading to productivity losses and missed opportunities.
Price and Content Scraping
Bots can extract pricing data and proprietary content from websites without permission, which can erode a company’s competitive edge. Competitors may use this data to undercut prices in real time, manipulating market dynamics and reducing profit margins. Content scraping can also lead to brand dilution when proprietary content is reused elsewhere without attribution.
High-frequency scraping can strain infrastructure, leading to slower load times for legitimate users. It also poses compliance risks when protected content is extracted in violation of terms of service or intellectual property laws.
Negative Impact on Online User Experience
Bots degrade user experience by slowing down websites or blocking access during peak activity. During product launches or high-demand events, scalper bots can buy out inventory before real users get a chance, frustrating customers and diminishing trust in the platform.
Additionally, spambots can flood comment sections or user-generated content platforms with irrelevant or malicious material. This diminishes the quality of interactions and forces users to navigate through noise, reducing engagement and satisfaction.
Distorted Web Analytics Data
Malicious bots inflate traffic metrics, such as page views and session counts, giving marketing and analytics teams an inaccurate picture of user behavior. This leads to poor decision-making based on faulty data, including misguided advertising spend and UX optimizations that don’t benefit real users.
Bot activity can also skew conversion rates and engagement statistics, complicating A/B testing and other forms of experimentation. Without proper filtering, analytics platforms may treat bot interactions as legitimate, masking real trends and issues.
Credential Stuffing Attacks
Credential stuffing attacks involve using automated bots to verify lists of stolen usernames and passwords against different service accounts. These credentials often come from data breaches where information has been leaked online. Attackers aim to gain unauthorized access, taking advantage of users who reuse passwords across multiple sites. Organizations with large user data sets are at high risk of this attack, as bots can test thousands of credentials within minutes.
Phishing Bot Attacks
Phishing bots distribute deceptive communications to trick recipients into divulging personal and financial information. These bots automate the personalization and delivery processes, making each phishing attempt seem increasingly legitimate. They target unsuspecting users through emails or messages with links to fake sites posing as authentic.
Carding and Credit Card Testing Bots
Carding involves using bots to validate stolen credit card information by performing small transactions. Successful transactions confirm the card's viability for larger fraudulent activities. This attack can drain funds, result in chargebacks, and leave organizations entangled with fraud investigations. Organizations in e-commerce are particularly vulnerable to these activities.
Web Scraping Bots
Web scraping bots extract content and data from websites without authorization or defeat website terms of service. While some web scraping can be legitimate, unauthorized scraping is often used to steal intellectual property, pricing data, or proprietary content.
Spambots and Spam Attacks
Spambots automate the distribution of unsolicited messages across forums, social media, and email systems. The objective is to spread advertising, malicious links, or phishing content en masse. They can undermine the trust and user experience on platforms, bringing regulatory challenges and potential sanctions for non-compliance.
Scalper Bots and Ticketing Fraud
Scalper bots purchase limited-availability goods, such as event tickets, in bulk at high speeds, intending to resell them at inflated prices. This behavior undermines genuine consumer access to products and contributes to unfair market conditions. Scalper bots impact brands by associating them with negative customer experiences and trust issues.
Click Fraud Bots
Click fraud bots generate fraudulent clicks on ads to deplete advertising budgets and skew analytics. These attacks can increase expenses for organizations engaging in pay-per-click advertising models while delivering no actual customer engagement. The results are distorted campaign metrics and potential financial losses.
Distributed Denial of Service (DDoS) Attacks
DDoS attacks leverage networks of bots, called botnets, to flood a service with traffic, rendering it unresponsive to legitimate users. Attackers aim to disrupt organizations by overwhelming their digital infrastructure, causing service outages and reputational damage. These attacks can last from a few hours to several days, depending on the attackers' objectives and resources.
Learn more in our detailed guide to anti DDoS solutions.
Bot attacks typically follow a structured approach, progressing through distinct phases:
- Reconnaissance: Attackers begin by gathering information about the target’s infrastructure, identifying vulnerabilities that can be exploited. This includes scanning for open ports, analyzing network architecture, and assessing existing security defenses. By understanding the target’s weaknesses, attackers can determine the most effective methods for bypassing security measures.
- Attack execution: Once reconnaissance is complete, attackers deploy bots to carry out the attack. They may use custom scripts, solver services, or large-scale botnets to automate malicious activities. The nature of the attack depends on the objective—DDoS attacks overwhelm servers, credential stuffing exploits leaked login credentials, and scraping bots extract proprietary data. Attackers often adjust the frequency and duration of attacks to evade detection and maximize damage.
- Retooling: If the initial wave of the attack is blocked, attackers analyze the defenses and modify their approach. They reverse-engineer security measures, adjust bot behavior, and attempt to bypass mitigation techniques. This iterative process continues until either the attack succeeds or defenses become too costly and complex to overcome. Security teams must recognize this ongoing adaptation and implement dynamic countermeasures to stay ahead.
- Impact: Successful attacks can result in account takeovers, service disruptions, financial losses, and reputational damage. Organizations that fail to implement resilient security measures may become repeated targets, as attackers prefer weakly defended systems. By continuously refining defenses and making retooling prohibitively difficult, businesses can deter attackers and protect their assets.
There are several issues that may indicate the presence of a bot attack:
- Unusual network activity: Anomalous spikes in network traffic, unauthorized access attempts, or abnormally high server requests often indicate a bot attack in action. Such activity may come from unknown IP addresses or outside normal business hours, suggesting malicious intent.
- Spike in failed login attempts: An abnormal increase in unsuccessful login attempts can signify credential stuffing attempts. This pattern typically involves repeated, rapid attempts to breach user accounts using leaked passwords.
- Sudden website performance issues: Unexpected website slowdowns or outages may result from bot activities like DDoS attacks. These performance issues disrupt user experiences, potentially leading to customer churn and financial losses.
- Unusual spikes in API traffic: A sudden increase in API calls, especially outside of peak hours, may indicate bot-driven abuse, such as credential stuffing or automated scraping.
- Abnormal account creation patterns: A surge in new account sign-ups with similar email structures or repetitive user behaviors suggests automated bot registrations, commonly used for fraud or spam.
- Increased chargebacks and fraudulent transactions: A rise in disputed payments or suspicious transactions can indicate bot-driven carding attacks attempting to validate stolen payment information.
- Irregular browsing behavior: Bots often exhibit non-human interaction patterns, such as rapid page switching, identical session durations, or high-speed form submissions. Behavioral analytics can help detect such anomalies.
Here are some of the ways that organizations can protect themselves against bot attacks.
1. Utilize Multi-Factor Authentication (MFA)
Adopting MFA bolsters security by requiring additional verification steps before granting access. This approach mitigates the risk of unauthorized access even if credentials are compromised. MFA disrupts bot attacks that rely on credential stuffing by rendering stolen passwords insufficient for access.
Organizations should integrate MFA into their access management protocols across systems and applications. Educating users on the importance and usage of MFA also improves engagement and adherence, reinforcing overall security posture against potential bot threats.
2. Regularly Update and Patch Systems
Routine updates and patch management close security vulnerabilities that bots commonly exploit. These practices are critical for maintaining a secure environment by addressing software flaws before they are leveraged maliciously. Scheduled patch cycles protect against new threats and minimize the attack surface.
Automating the patching process ensures timely deployments and reduces human error. Complementary measures, such as vulnerability scanning, provide proactive insight into potential weaknesses, enabling rapid corrective action and sustained operational security.
3. Apply Rate Limiting and Traffic Filtering
Rate limiting restricts the number of requests a user can make to a service within a specified time, deterring automated attacks. Implementing traffic filtering at strategic checkpoints can help identify and isolate harmful bot activities from legitimate traffic. These techniques maintain performance by preventing systems from overwhelming through moderation.
Continuous adjustment of limits based on analysis and historical data ensures optimal user experience while maintaining security. Aligning limits with business processes and operational needs improves security without disrupting users or negatively impacting performance.
4. Employ Web Application Firewalls (WAF)
WAFs provide an essential defense layer for filtering and monitoring HTTP requests to web applications. They protect against SQL injections, cross-site scripting, and DDoS, effectively blocking incoming threats from bots. WAF technology analyzes traffic patterns to prevent malicious activity before it reaches critical infrastructure.
To maximize effectiveness, organizations must configure WAFs according to their threat landscapes and business requirements. Collaboration with threat intelligence feeds and regular tuning provide adaptive defenses capable of thwarting sophisticated bot networks.
5. Using a DDoS Protection Solution to Protect Against High-Volume Application Layer Attacks
DDoS protection solutions identify and block high-volume traffic aimed at overwhelming application resources. These tools analyze incoming traffic in real time, distinguishing between legitimate users and malicious bots using behavior-based heuristics and traffic signatures. By rerouting or absorbing attack traffic, they help maintain service availability and performance.
Advanced solutions often integrate with content delivery networks (CDNs) and employ global scrubbing centers to handle attacks closer to their origin. Organizations benefit from automated response mechanisms, rate controls, and adaptive filtering that reduce response time and protect critical applications under load.
6. Implement Bot Detection and Management Solutions
Deploying bot detection systems is essential to identify and manage both good and malicious bots effectively. These solutions leverage machine learning and behavior analytics to differentiate between human users and automated scripts accurately.
Regular updates to detection algorithms and systems ensure they adapt to evolving bot strategies. By integrating detection capabilities with broader security architectures, organizations can enforce consistent policies across digital environments, fortifying defenses further.
Related content: Read our guide to botnet detection
Radware offers a range of solutions to effectively detect and mitigate bot attacks:
Bot Manager
Radware Bot Manager is a multiple award-winning bot management solution designed to protect web applications, mobile apps, and APIs from the latest AI-powered automated threats. Utilizing advanced techniques such as Radware’s patented Intent-based Deep Behavior Analysis (IDBA), semi-supervised machine learning, device fingerprinting, collective bot intelligence, and user behavior modeling, it ensures precise bot detection with minimal false positives. Its AI-powered correlation engine automatically analyzes threat behavior, shares data throughout security modules and blocks bad source IPs, providing complete visibility into each attack. Bot Manager protects against threats such as ATO (account takeover), DDoS, ad and payment fraud, web scraping, and unauthorized API access. Bot Manager ensures seamless website access for legitimate users without relying on CAPTCHAs. It also provides a range of customizable mitigation options including Crypto Challenge that thwarts attacks by exponentially increasing the computing power needed by attackers. With a scalable infrastructure and a detailed dashboard, Radware Bot Manager delivers real-time insights into bot traffic, helping organizations safeguard sensitive data, maintain user trust, and prevent financial fraud.
Alteon Application Delivery Controller (ADC)
Radware’s Alteon Application Delivery Controller (ADC) offers robust, multi-faceted application delivery and security, combining advanced load balancing with integrated Web Application Firewall (WAF) capabilities. Designed to optimize and protect mission-critical applications, Alteon ADC provides comprehensive Layer 4-7 load balancing, SSL offloading, and acceleration for seamless application performance. The integrated WAF defends against a broad range of web threats, including SQL Injection, cross-site scripting, and advanced bot-driven attacks. Alteon ADC further enhances application security through bot management, API protection, and DDoS mitigation, ensuring continuous service availability and data protection. Built for both on-premises and hybrid cloud environments, it also supports containerized and microservices architectures, enabling scalable and flexible deployments that align with modern IT infrastructures.
DefensePro X
Radware's DefensePro X is an advanced DDoS protection solution that provides real-time, automated mitigation against high-volume, encrypted, and zero-day attacks. It leverages behavioral-based detection algorithms to accurately distinguish between legitimate and malicious traffic, enabling proactive defense without manual intervention. The system can autonomously detect and mitigate unknown threats within 18 seconds, ensuring rapid response to evolving cyber threats. With mitigation capacities ranging from 6 Gbps to 800 Gbps, DefensePro X is built for scalability, making it suitable for enterprises and service providers facing massive attack volumes. It protects against IoT-driven botnets, burst attacks, DNS and TLS/SSL floods, and ransom DDoS campaigns. The solution also offers seamless integration with Radware’s Cloud DDoS Protection Service, providing flexible deployment options. Featuring advanced security dashboards for enhanced visibility, DefensePro X ensures comprehensive network protection while minimizing operational overhead.
Cloud DDoS Protection Service
Radware’s Cloud DDoS Protection Service offers advanced, multi-layered defense against Distributed Denial of Service (DDoS) attacks. It uses sophisticated behavioral algorithms to detect and mitigate threats at both the network (L3/4) and application (L7) layers. This service provides comprehensive protection for infrastructure, including on-premises data centers and public or private clouds. Key features include real-time detection and mitigation of volumetric floods, DNS DDoS attacks, and sophisticated application-layer attacks like HTTP/S floods. Additionally, Radware’s solution offers flexible deployment options, such as on-demand, always-on, or hybrid models, and includes a unified management system for detailed attack analysis and mitigation.