Summary
Bots and fake data infiltrate web forms for a multitude of reasons, ranging from targeted malicious attacks to unintended consequences of automated web crawling. A primary motivation for bots is to conduct various forms of spam, including harvesting email addresses for future campaigns, executing SEO spam by injecting unwanted links or keywords, and distributing malware or phishing links. Bots also frequently create fraudulent accounts for purposes like credential stuffing, list bombing-where they subscribe stolen email addresses to overwhelm inboxes and obscure security alerts-or to exploit free services. Beyond these, their objectives can include testing website vulnerabilities, consuming server resources through denial-of-service attacks, and gathering competitive intelligence. While many submissions originate from untargeted bots that simply hit any vulnerable endpoint, some are highly sophisticated, demonstrating multi-stage behaviors across different IP addresses. It's not just bots, however; humans also contribute to fake data, whether intentionally submitting false information to avoid unwanted communications or as part of incentivized, low-quality lead generation efforts. This influx of invalid data poses significant challenges for email marketers, directly impacting deliverability and data integrity.
Key findings
- Diverse Malicious Intent: Bots submit web forms for a wide array of malicious purposes, including harvesting email addresses for spam campaigns, performing SEO spam by injecting links, distributing malware, launching phishing attacks, and creating fraudulent accounts for scams or credential stuffing. Some bots aim to overwhelm servers or hide notifications related to account takeovers.
- Collateral Damage & Confusion: Beyond direct attacks, bots may submit fake data due to confusion. For example, web crawling bots designed for comment sections might fill out subscribe forms with garbage data if they detect common fields like 'FirstName' or 'Email', inadvertently affecting message recipients rather than directly targeting the business itself.
- Human-Driven Invalid Data: Not all fake data comes from bots; real humans also contribute. Some individuals intentionally submit invalid email addresses to access gated content or receive quotes without incurring unwanted follow-up emails, particularly in industries like insurance. Additionally, services like Mechanical Turk pay real people to fill out forms, sometimes leading to low-quality or invalid submissions.
- Sophisticated Automated Behavior: Modern bot activity can be highly sophisticated, involving multi-stage processes such as signing up from one IP address and then logging in seconds later from a completely different one. This complex behavior is designed to bypass basic security measures and mimic legitimate user actions.
- Impact on Deliverability: Fake form submissions directly impact email deliverability. They can lead to high bounce rates, increased spam complaints when email addresses are used for list bombing to hide alerts about compromised accounts, and damage to sender reputation due to engagement with invalid or stolen email addresses.
Key considerations
- Enhanced Security: Implementing robust security measures like CAPTCHAs, honeypots, and behavioral analysis is crucial to deter automated bot submissions. These tools can help differentiate between legitimate users and malicious traffic, reducing the volume of fake data and spam.
- Data Validation: Regularly validate email addresses and other submitted data fields. Utilizing real-time email verification services and performing ongoing list hygiene can help identify and remove invalid or fake entries, preserving the integrity of your marketing database and improving deliverability.
- Monitoring Anomalies: Continuously monitor web form submission patterns for unusual spikes in volume, rapid consecutive submissions from single IP addresses, or logins from disparate geographical locations immediately after signup. Such anomalies can indicate bot activity or sophisticated automated attacks.
- Vendor Diligence: Exercise caution and conduct thorough due diligence when engaging third-party lead generation vendors. Ensure their practices align with ethical data collection standards to avoid receiving incentivized fake data or leads sourced from bot-infected machines, which can harm your sender reputation.
What email marketers say
13 marketer opinions
Web forms are frequently targeted by automated bots and, at times, by human actors entering inaccurate information, driven by a range of motivations. Bots commonly seek to compromise systems or harvest data; their objectives include collecting email addresses for spam, executing SEO spam by inserting unwanted links or keywords, and spreading malware or phishing content. They also aim to create fake accounts for credential stuffing or other forms of abuse, and to stress server infrastructure. While some bot activities are untargeted, hitting any vulnerable form, others display advanced behaviors, like signing up from one IP address and logging in from another shortly after. Beyond bots, individuals sometimes input false data, either to gain access to gated content without receiving follow-up communications or as part of low-quality, incentivized data collection efforts. This influx of invalid data poses significant challenges for maintaining clean marketing lists and achieving strong email deliverability.
Key opinions
- Diverse Malicious Objectives: Bots submit web forms for a broad spectrum of malicious purposes, including harvesting email addresses for spam campaigns, injecting SEO spam (like backlinks or keywords) into websites, distributing malware, launching phishing attacks, and creating fraudulent accounts for various abuses.
- System Exploitation and Resource Consumption: Beyond data theft, bots aim to exploit system vulnerabilities, consume server resources through high-volume submissions (potentially leading to denial-of-service), and generate fake leads that can be sold to unsuspecting businesses, causing operational and financial harm.
- Sophisticated Automated Tactics: Modern bot activity can be highly advanced, exhibiting complex behaviors such as signing up from one geographic IP address (e.g., Vietnam) and then logging in seconds later from a completely different IP (e.g., a US-based AWS server), indicating multi-stage, coordinated automation.
- Human Contribution to Invalid Data: It's not exclusively bots; real people also contribute to invalid data. This occurs when individuals intentionally enter false email addresses to access gated content or quotes without wanting follow-up, or when services like Mechanical Turk pay people to fill out forms, sometimes leading to low-quality or irrelevant submissions.
- Direct Impact on Email Deliverability: The influx of bot-generated and human-entered fake data directly harms email deliverability. It leads to high bounce rates, increased spam complaints (especially when email addresses are 'list bombed' to bury legitimate notifications), and a damaged sender reputation due to engagement with non-existent or compromised addresses.
Key considerations
- Implement Robust Form Security: To combat both sophisticated bots and untargeted web crawlers, deploy multi-layered security measures such as CAPTCHAs, honeypots, and real-time behavioral analysis. These tools are crucial for filtering out automated submissions designed for spam, fraud, or system disruption.
- Prioritize Data Validation and Hygiene: Given that both bots and humans contribute to invalid data, consistently validate all submitted information, especially email addresses. Employ real-time email verification at the point of submission and perform regular list hygiene to remove bad data, thereby preserving list quality and protecting sender reputation.
- Monitor for Complex Attack Patterns: Be vigilant for advanced bot behaviors, such as sign-ups from one IP address followed by immediate logins from a different, unrelated IP. Detecting such multi-stage patterns requires sophisticated monitoring and analytics to identify and block coordinated attacks.
- Understand Human Motivation for False Data: Recognize that not all invalid data comes from bots; some originates from real people intentionally inputting false information to bypass gates or avoid follow-up communications. Consider offering clear alternatives for content access or using progressive profiling to reduce the incentive for users to submit false details.
Marketer view
Email marketer from Email Geeks explains that bots submit forms for hacker reasons, such as to overload web servers and expose vulnerabilities, or to hijack a company's email deliverability by flooding inboxes to bury important notifications related to compromised accounts. She notes that bots often webcrawl and are not targeted, hitting any endpoint without a CAPTCHA.
13 Jun 2022 - Email Geeks
Marketer view
Email marketer from Email Geeks adds that platforms like Mechanical Turk pay real people to fill out forms and even solve CAPTCHAs, contributing to the issue of invalid data.
22 Feb 2022 - Email Geeks
What the experts say
4 expert opinions
Bots and various forms of fake data are submitted through web forms for a diverse set of reasons, encompassing malicious attacks, deceptive practices, and even unintentional actions. A primary motive for automated bots is to generate different kinds of spam-like comment, registration, or contact form spam-and to create fraudulent accounts for activities such as credential stuffing, list bombing (which aims to conceal account takeovers or other fraudulent notifications), or to exploit free services. These bots also work to scrape data, test websites for vulnerabilities, or compromise data integrity by flooding systems with large volumes of false information. Beyond automated threats, human actors contribute to the problem by intentionally providing invalid details, often to avoid unwanted communications or as part of low-quality, incentivized lead generation efforts. All these actions ultimately impact message recipients and email deliverability.
Key opinions
- Diverse Malicious Bot Goals: Bots submit web forms to generate various forms of spam, including comment, registration, and contact form spam. They also create fake accounts for purposes like credential stuffing, list bombing to hide account takeovers or fraud, and exploiting free services.
- Data Exploitation and Disruption: Automated bots use forms to scrape data, test for website vulnerabilities, and disrupt data integrity by overwhelming systems with fake information. They can also assess sender list hygiene and reputation, or prepare for future phishing attacks.
- Unintentional Bot Submissions: Some bots, designed for web crawling or leaving comments, may mistakenly fill out subscribe forms with irrelevant data if they detect common fields like 'FirstName' or 'Email', inadvertently affecting email recipients rather than directly targeting the business.
- Human Contribution to Invalid Data: Not all fake data is bot-generated; humans also intentionally provide invalid email addresses to obtain quotes or access content without follow-up. Additionally, third-party lead generation vendors might supply fake data, sometimes from bot-infected sources, driven by payment incentives.
- Impact on Email Deliverability: The influx of fake and invalid submissions directly harms email deliverability, resulting in higher bounce rates, increased spam complaints, especially from list bombing attempts, and damage to sender reputation.
Key considerations
- Enhance Form Security: To counter spam, fake accounts, and data disruption, implement robust form security measures such as CAPTCHAs, honeypots, and advanced behavioral analysis to filter out automated submissions effectively.
- Prioritize Data Validation: Consistently validate all submitted data, particularly email addresses, through real-time verification and ongoing list hygiene. This helps maintain data integrity, reduce bounce rates, and protect sender reputation.
- Address Human-Sourced Invalidity: Understand the motivations behind humans submitting fake data. Offer clear consent options, transparent privacy policies, and vet lead generation vendors rigorously to avoid acquiring incentivized low-quality or bot-sourced data.
- Monitor for Account Abuse: Actively monitor for signs of account abuse like list bombing or unusual submission patterns that could indicate attempts to hide fraudulent activity or test email validity. Rapid detection and response are crucial for protecting legitimate users and your sender reputation.
Expert view
Expert from Email Geeks shares that bots use email flooding to hide notifications during account takeovers or hacks. He also states that many bots that leave website comments can get confused and fill out subscribe forms with garbage data if they detect fields like FirstName, LastName, or Email, emphasizing that their actions are not always about the business itself but about affecting message recipients.
3 Mar 2022 - Email Geeks
Expert view
Expert from Email Geeks explains that if companies pay vendors to funnel traffic or leads, those vendors may be incentivized to provide fake data, often generated by outsourced and bot-infected Windows machines. She adds that in industries like insurance lead generation, people frequently submit invalid email addresses because they want quotes but not the follow-up emails, knowing their address will be widely shared.
24 Sep 2022 - Email Geeks
What the documentation says
5 technical articles
Bots target web forms for a spectrum of malicious objectives, often as a critical initial step in broader attack campaigns. These automated submissions are driven by the desire to create fraudulent accounts for subsequent spam, scams, or other illicit activities. Bots also aim to bypass security measures, enabling them to generate high volumes of spam, disrupt website operations, or overwhelm systems. Common attack vectors include content scraping, credential stuffing, and account takeover attempts. Furthermore, forms are leveraged for general spamming, as part of distributed denial-of-service, DDoS, attacks, for testing stolen credentials, account aggregation, payment card fraud, vulnerability scanning, and data theft, frequently seeking to exploit weaknesses or gain unauthorized access.
Key findings
- Fraudulent Account Creation: Bots frequently submit web forms to create fraudulent accounts, which serve as an initial step in broader attack chains for spamming, scams, or other malicious activities.
- Security Bypass and System Overload: A primary bot motivation is to bypass security measures like reCAPTCHA, enabling them to generate large volumes of spam, disrupt legitimate website operations, or overwhelm systems with excessive submissions.
- Credential Stuffing and Account Takeover: Web forms are a common target for credential stuffing attacks, where bots test stolen login details, and for direct account takeover attempts, aiming to gain unauthorized access.
- Data Exploitation and Vulnerability Probing: Bots utilize forms for content scraping, data theft, and performing vulnerability scans. These actions aim to identify weaknesses for future exploitation or to acquire sensitive information.
- Spam Generation and DDoS Attacks: Beyond specific targeted attacks, forms are exploited for general spamming and as a component of distributed denial-of-service, DDoS, attacks, designed to disrupt service availability or functionality.
Key considerations
- Implement Advanced Bot Protection: To effectively combat fraudulent account creation, spam generation, and system disruption, deploy advanced bot management solutions. These should include behavioral analysis, robust CAPTCHAs, and honeypots to identify and block sophisticated automated form submissions.
- Monitor for Account Abuse: Actively monitor web form submission and login patterns for unusual activities indicative of credential stuffing, account aggregation, or large-scale fraudulent account creation. Rapid detection is key to mitigating potential damage.
- Secure Forms Against Exploitation: Regularly audit web forms for potential vulnerabilities that bots could exploit for data theft, unauthorized access, or to launch distributed denial-of-service, DDoS, attacks. Ensure forms are hardened against known automated threats.
- Safeguard User Information: Implement preventative measures to protect web forms from being used for content scraping and data theft. This safeguards sensitive user information and helps maintain trust with your legitimate audience.
Technical article
Documentation from Akamai Technologies details that bots submit web forms as part of broader bot attacks such as creating fraudulent accounts, which can be used for subsequent spam, scams, or other malicious activities. This is often an initial step in a larger attack chain.
1 Apr 2025 - Akamai
Technical article
Documentation from Google Developers explains that bots submit web forms to bypass security measures like reCAPTCHA, enabling them to generate large volumes of spam, create fraudulent user accounts, and disrupt legitimate website operations by overwhelming systems.
12 Oct 2022 - Google Developers
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