How are bad actors using Google Forms to send spam?

Summary

Bad actors exploit Google Forms for spam by leveraging various methods. These include using automated bots to rapidly submit forms with malicious links or content, harvesting user data (especially email addresses) for phishing campaigns, and misusing Google Apps Script to automate and send high volumes of unsolicited emails. They also exploit the ease of creating and distributing forms. The spam originates from genuine Google mail servers, making it appear legitimate. This activity impacts email deliverability, potentially leading to blocklisting. Countermeasures include CAPTCHAs, rate limiting, honeypots, bot management tools, robust form validation, and monitoring script usage.

Key findings

  • Genuine Source Abuse: Spammers send spam through legitimate Google mail servers, making it harder to detect.
  • Automation at Scale: Automated tools are used to rapidly submit forms, exploiting vulnerabilities in form security.
  • Data Harvesting for Phishing: Forms are used to collect email addresses and other data for phishing and spam campaigns.
  • Apps Script Misuse: Google Apps Script is exploited to send large volumes of spam emails.
  • Deliverability Impact: Form spam can lead to reduced email deliverability and potential blocklisting.

Key considerations

  • Implement CAPTCHAs: Use CAPTCHAs to differentiate between humans and bots, reducing automated spam.
  • Employ Bot Management: Utilize bot management tools to identify and mitigate malicious bot traffic.
  • Use Rate Limiting: Limit form submissions from a single source to prevent abuse.
  • Enhance Form Validation: Implement strong form validation to block malicious content and irrelevant submissions.
  • Monitor Script Activity: Monitor Google Apps Script usage to detect and prevent spam-related abuse.
  • Deploy Honeypots: Use honeypots to trap and block spam bots.

What email marketers say
8Marketer opinions

Bad actors exploit Google Forms in several ways to send spam. They use automated bots to rapidly submit forms with malicious links or content, harvest user data (especially email addresses) for phishing campaigns, and leverage Google Apps Script to automate and send high volumes of unsolicited emails. The ease of creating and distributing forms contributes to the abuse, while CAPTCHAs and bot management tools offer mitigation strategies.

Key opinions

  • Automated Bots: Spammers use automated bots to submit forms quickly and at scale, overwhelming form owners with malicious content.
  • Data Harvesting: Forms are used to collect email addresses and other user information, which is then used for phishing or spam campaigns.
  • Apps Script Abuse: Google Apps Script can be misused to automate the sending of a large number of spam emails from form submissions.
  • Malicious Links: Spam forms often contain malicious links designed to trick users into visiting harmful websites.
  • Ease of Use Exploitation: The simplicity of creating and distributing Google Forms makes them an attractive target for spammers.

Key considerations

  • Implement CAPTCHAs: Use CAPTCHAs to help distinguish between human users and bots, reducing automated spam submissions.
  • Bot Management Tools: Employ bot management tools to identify and mitigate malicious bot traffic targeting forms.
  • Monitor Apps Script Usage: Carefully monitor and restrict the usage of Google Apps Script to prevent abuse for spamming purposes.
  • Form Validation: Implement robust form validation to prevent the submission of malicious or irrelevant content.
  • User Awareness: Educate users to recognize and avoid clicking on suspicious links in forms or providing sensitive information.
Marketer view

Email marketer from Reddit explains that spammers use Google Forms to collect email addresses and other information, which they then use to send unsolicited emails. The form itself may also contain spam links or requests for sensitive information.

August 2022 - Reddit
Marketer view

Email marketer from Digital Trends shares that it's relatively simple to create a Google Form and then distribute it widely. Spammers exploit this to send out forms with malicious links or to harvest user data.

August 2021 - Digital Trends
Marketer view

Email marketer from WPForms explains how spammers use automated bots to submit forms, often with malicious links or content. The automated submissions can be overwhelming and time-consuming to manage.

March 2024 - WPForms
Marketer view

Email marketer from Cloudflare shares how bot management identifies and mitigates malicious automated traffic that attempts to perform undesirable actions, such as spamming via forms.

February 2024 - Cloudflare
Marketer view

Email marketer from MailerLite shares that bad actors can use bots to fill out Google Forms with malicious content or links. They also explain that spammers could also use forms to collect information like emails to send phishing attempts.

April 2024 - MailerLite
Marketer view

Email marketer from Formspree discusses the methods of spambots that exploit forms, explaining that they can automatically and rapidly complete forms to send out phishing emails, promote scams, and distribute malware.

June 2022 - Formspree
Marketer view

Email marketer from EmailToolTester mentions that CAPTCHA can mitigate automated spam form submissions, but also that the forms can be used to collect info for phishing.

August 2023 - EmailToolTester
Marketer view

Email marketer from Stack Overflow shares that Google Apps Script allows you to send emails from Google Forms responses. While legitimate, it can be exploited to automate and send a high volume of spam emails if malicious scripts are used.

February 2025 - Stack Overflow

What the experts say
3Expert opinions

Bad actors are using Google Forms to send spam through genuine Google mail servers. This is achieved by exploiting vulnerabilities in form validation and CAPTCHA implementations, often using automated tools to rapidly submit forms. This spam impacts email deliverability, potentially leading to emails being classified as spam and the sender's IP or domain being added to blocklists.

Key opinions

  • Legitimate Source Abuse: Spammers leverage Google's own infrastructure to send spam, making it appear legitimate.
  • Automation Exploitation: Automated tools are used to rapidly fill out and submit forms, bypassing security measures.
  • Deliverability Impact: Spam sent through forms can negatively affect overall email deliverability, leading to blocklisting.

Key considerations

  • Strengthen Form Security: Implement robust form validation and CAPTCHA systems to prevent automated submissions.
  • Monitor Form Activity: Actively monitor form submissions for suspicious activity and potential spam.
  • Deliverability Protection: Take steps to protect your email deliverability by preventing your domain or IP from being associated with form spam.
Expert view

Expert from Spam Resource explains that spammers use automated tools to fill out forms rapidly and at scale, exploiting vulnerabilities in form validation and CAPTCHA implementations.

April 2024 - Spam Resource
Expert view

Expert from Email Geeks explains that the email is genuine Google mail, sent from Google servers and authenticated by google.com. It appears a bad actor is using Google Forms to send spam.

October 2021 - Email Geeks
Expert view

Expert from Word to the Wise explains that contact form spam impacts deliverability. Email programs may interpret messages as spam and you can also be added to blocklists if you have excessive amounts of spam. Also the IP or the domain of the contact form can be added to blocklists.

January 2025 - Word to the Wise

What the documentation says
4Technical articles

Google Forms are vulnerable to abuse, including spam and phishing. This can be mitigated by employing security measures like reCAPTCHA, rate limiting, and honeypots to distinguish between legitimate users and automated bots. Google actively monitors script usage to prevent spamming, but proactive measures are essential for form protection.

Key findings

  • Abuse Potential: Google Forms, like other online tools, are susceptible to abuse for sending unsolicited content and phishing attempts.
  • Script Vulnerability: Scripts that can send large amounts of email are prone to abuse, requiring monitoring to prevent spam.
  • reCAPTCHA Effectiveness: reCAPTCHA helps differentiate between humans and bots, blocking automated software from abusing forms.
  • Multi-Layered Protection: CAPTHCHAs, rate limiting, and honeypots enhance form security against automated attacks.

Key considerations

  • Implement reCAPTCHA: Add reCAPTCHA to forms to distinguish between humans and bots, reducing automated submissions.
  • Utilize Rate Limiting: Apply rate limiting to restrict the number of submissions from a single source within a given timeframe.
  • Employ Honeypots: Use honeypots as decoy form fields to trap and block spam bots.
  • Monitor Script Activity: Regularly monitor and manage script usage associated with Google Forms to detect and prevent abuse.
Technical article

Documentation from Google Support explains that Google Forms, like any online tool, can be abused to send unsolicited or unwanted content, violating Google's policies. Abuse can range from spam to phishing attempts.

October 2024 - Google Support
Technical article

Documentation from Google Developers explains that scripts have the ability to send large amounts of email, and so are subject to abuse. Google actively monitors script usage to prevent spamming.

October 2021 - Google Developers
Technical article

Documentation from Google explains that reCAPTCHA helps to protect forms from spam and abuse by using advanced risk analysis techniques to tell humans and bots apart. By adding reCAPTCHA to a form, you can block automated software while still allowing your welcome users to pass through with ease.

September 2024 - Google
Technical article

Documentation from OWASP explains how to protect forms with CAPTCHAs, rate limiting, and honeypots to make it harder for automated bots to abuse the forms and send spam.

November 2023 - OWASP