Summary
Hidden links in emails frequently register high click rates from bots and automated systems primarily because email security software, spam filters, and corporate gateways proactively scan all links for malicious content. These systems employ advanced techniques like pre-fetching and sandboxing, where URLs are 'clicked' and analyzed in isolated environments to identify phishing, malware, or other threats before the email reaches the recipient. This automated, protective process generates recorded clicks from non-human sources, which is a normal function of modern email security.
Key findings
- Security System Scans: Email security software, anti-spam filters, and corporate gateways from providers like Microsoft Defender (Safe Links), Mimecast, Barracuda, Proofpoint, and Cisco Talos automatically scan and click all links, including hidden ones, to detect threats.
- Proactive Threat Detection: These automated systems employ techniques such as sandboxing and pre-fetching, executing URLs in isolated environments to simulate user clicks and analyze link behavior for malicious content, phishing, or malware before the email reaches the user.
- Pre-Delivery Analysis: The clicks are generated by the security infrastructure itself as part of a pre-delivery analysis. This means the clicks occur before the email is even seen by the recipient, ensuring safety from potentially harmful content.
- Common Industry Practice: Automated link scanning is a widespread practice among major email providers, such as Google and Microsoft 365, and corporate email security appliances, making these bot clicks a common occurrence for marketers.
Key considerations
- Analyze Click Data: Examine detailed click data, including user agents, IP addresses, and browser information, to identify automated clicks and distinguish them from genuine human engagement. This helps in pinpointing the specific security services or systems generating the clicks.
- Expect Automated Scans: Recognize that automated clicks on hidden links are a standard security measure. This phenomenon is a sign that email gateways and security software are working to protect recipients, rather than an indication of unusual recipient behavior.
- Adjust Analytics: Account for bot clicks when analyzing email campaign performance. These automated interactions can inflate click-through rates, so it's important to filter out or segment such clicks for a more accurate understanding of human engagement.
What email marketers say
12 marketer opinions
Modern email security systems, including those deployed by major email service providers and corporate networks, are the primary cause of high click rates on hidden links from bots. These advanced defenses go beyond simple spam detection; they proactively analyze all URLs within an email- whether visible or intentionally hidden- by pre-fetching, sandboxing, and even 'detonating' links in isolated environments. This comprehensive scanning aims to uncover sophisticated threats like malicious redirects, phishing attempts, and malware before the message reaches a user's inbox, ensuring a safer email experience by validating all potential destinations.
Key opinions
- Advanced Security Scans: Email security solutions, including corporate gateways and specific features from providers like Outlook's Safelinks and Gmail's security scans, proactively 'click' and analyze all links, visible or hidden, to detect malware, phishing, and hidden threats.
- Proactive Link Detonation: Systems such as Proofpoint, Barracuda, and Microsoft 365 often employ sandbox environments to 'detonate' or pre-fetch URLs, simulating user interaction to assess link behavior and identify malicious redirects before delivery to recipients.
- Universal Link Validation: Regardless of a link's visibility or placement within an email, automated security systems are designed to crawl and evaluate every URL, ensuring a thorough check for safety and legitimacy before the email reaches the end-user.
- Pre-Delivery Protection: These clicks are generated by automated security agents as part of a pre-delivery screening process, meaning the interaction occurs before the email is delivered to the recipient's inbox, safeguarding against potential threats.
Key considerations
- Segment Automated Clicks: To gain accurate insights into human engagement, marketers should segment or filter out automated clicks, recognizing that inflated click-through rates from security scans do not represent genuine recipient interest or interaction.
- Leverage Analytics Data: Utilize detailed analytics- user agents, IP addresses, and browser data- to identify the specific security services or corporate systems, like Barracuda or Microsoft 365, that are generating these automated link clicks.
- Standard Security Behavior: Understand that high click rates on hidden links are a normal, protective function of modern email security, indicating that recipients' inboxes are being actively defended against evolving cyber threats.
Marketer view
Marketer from Email Geeks explains that B2B Enterprise email filters often click links to analyze their destination, suggesting this as a reason for unexpected clicks on hidden links. He also advises examining user agents for more data.
2 Nov 2023 - Email Geeks
Marketer view
Marketer from Email Geeks shares that by tracking detailed data like user agents, browser, and IP, it's possible to identify automated clicks originating from security services, citing examples like Barracuda or even Microsoft 365 (O365) scanning links.
20 Feb 2023 - Email Geeks
What the experts say
2 expert opinions
The elevated click rates on hidden email links from bots and automated systems stem from the protective functions of modern spam filters and email security products. These sophisticated systems are designed to automatically click every link within an email, irrespective of its visibility, as a critical part of their analysis. This process allows them to thoroughly scan for malicious content, detect phishing attempts, and assess sender reputation, thereby safeguarding recipients from potential threats before the email is delivered.
Key opinions
- Automated Link Scanning: Sophisticated spam filters and email security systems automatically click all links in an email, including hidden ones, as part of their comprehensive analysis process.
- Threat Detection Purpose: The primary goal of these automated clicks is to scan for malicious content, identify phishing attempts, and evaluate the sender's reputation and legitimacy.
- Indiscriminate Analysis: These security systems do not differentiate between visible and hidden links, treating all URLs equally in their automated evaluation for safety and compliance.
Key considerations
- Interpreting Click Data: When analyzing email performance, recognize that clicks on hidden links often originate from security bots, not human recipients. This requires careful interpretation of click-through rates.
- Security Functionality: High bot clicks on hidden links are a normal indication that email security systems are actively working to protect recipients by pre-screening all email content for threats.
- Adjusting Metrics: To get an accurate measure of human engagement, it's essential to factor in and account for these automated clicks, as they inflate overall click metrics without reflecting genuine interest.
Expert view
Expert from Spam Resource explains that many modern and sophisticated spam filters and email security systems click links within emails. They do this to scan for malicious content, identify phishing attempts, and evaluate sender reputation, which includes clicking any link, whether visible or hidden, as part of their automated analysis process.
8 Aug 2024 - Spam Resource
Expert view
Expert from Word to the Wise shares that numerous spam filter systems and email security products automatically click on all links present in an email, including hidden ones. This indiscriminate clicking is part of their evaluation process to check for malicious content, identify phishing, or perform general link analysis.
31 Jan 2025 - Word to the Wise
What the documentation says
7 technical articles
Automated clicks on hidden links within emails are a direct result of advanced security protocols implemented by email providers and corporate networks to safeguard recipients. These systems, including sophisticated spam filters and threat protection services, proactively 'click' and analyze all embedded URLs- regardless of their visibility- in isolated, sandboxed environments. This pre-delivery analysis is crucial for identifying and neutralizing phishing, malware, and other cyber threats before an email ever lands in a user's inbox.
Key findings
- Ubiquitous Link Scanning: Email security solutions across the industry, including those from Google, Microsoft, Mimecast, and Proofpoint, are engineered to automatically process all URLs within incoming emails, identifying and scrutinizing even hidden links.
- Simulated Clicks in Isolation: These systems routinely perform simulated clicks and pre-fetches of URLs within secure, sandboxed environments, a method designed to safely test link destinations for malicious content without risking actual user exposure.
- Pre-delivery Threat Neutralization: The core purpose of these automated clicks is to proactively detect and neutralize sophisticated cyber threats, such as phishing attempts and malware, ensuring that dangerous links are identified and blocked before the email ever reaches a recipient's inbox.
- Standard Security Protocol: The occurrence of bot clicks on hidden links is a normal, expected outcome of robust email security protocols, reflecting a widespread commitment across email service providers and corporate IT to protect users from evolving online threats.
Key considerations
- Refine Engagement Metrics: Email marketers must learn to differentiate bot-generated clicks on hidden links from genuine human interaction. This distinction is vital for accurately assessing campaign performance and understanding true recipient engagement, as automated clicks can skew overall CTRs.
- Investigate Click Origins: Utilize advanced email analytics to pinpoint the sources of these automated clicks. Analyzing data like user-agent strings, IP addresses, and referral information can help identify specific security solutions- such as those from Microsoft, Mimecast, or Barracuda- that are performing these scans.
- Acknowledge Security Efficacy: View high bot click rates on hidden links as confirmation that robust security mechanisms are actively safeguarding email recipients. This indicates effective protection against potentially malicious content, reinforcing the integrity of your email delivery to secure inboxes.
Technical article
Documentation from Google Workspace Admin Help explains that Google uses automated systems and Safe Browsing technology to scan inbound emails for malicious content, including links. These systems pre-fetch and analyze URLs in a sandboxed environment to identify phishing, malware, and other threats before the email reaches the user's inbox, which can register as a click.
8 Jul 2024 - Google Workspace Admin Help
Technical article
Documentation from Microsoft Learn details how Microsoft Defender for Office 365, particularly the Safe Links feature, proactively scans URLs in emails. When an email arrives, Safe Links processes all URLs, including hidden ones, in a sandbox environment, simulating user clicks to detect malicious behavior. This pre-scanning and detonation process generates click data before the user ever opens the email.
1 Sep 2021 - Microsoft Learn
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