Security when personalizing with Smarty

Smarty offers powerful capabilities to deliver relevant and engaging content to your audience. To ensure these processes are secure, it's important to follow some safety measures. By adhering to the following guidelines, you can maximize the benefits of personalization while safeguarding your data and your customers.

Where does your data come from?

As a template designer or email marketer, it's crucial to know where your data comes from and how to use it safely. Data from internal sources is usually reliable, but data from external sources or user input can be corrupted and should be carefully filtered. It's good practice to always use Smarty's |escape modifier to sanitize your data.

Additionally, keep in mind that email is an inherently insecure communication protocol. Emails can be intercepted, and recipients can accidentally or intentionally forward them to outsiders. Therefore, it's wise not to include all the information you have about your contacts in your mailings.

Some Guidelines

We've outlined some key security guidelines that you should always follow:

Always use the |escape modifier

Smarty's |escape modifier is a simple yet powerful way to display your dynamic content safely. It prevents malicious scripts from being executed in the recipient's email client. Here's an example:

Hello {$firstname|escape},

We have a special offer for you!

Using the |escape modifier ensures your data is safe and doesn't contain any unwanted HTML or JavaScript code. This protects you from potential attacks via your signup forms.

Verify and clean input

Besides the |escape modifier, it's important to validate and clean all the data you use in your templates. This means ensuring that all variables filled in by users or coming from external sources are checked for validity and don't contain dangerous content.

If you always run your data through the |escape modifier, this is essentially taken care of, but it's wise to regularly check your database and log files to see if anyone is trying to abuse the system.

Use only trusted data

Work only with trusted data sources and avoid directly including user input in templates without proper validation and sanitization. This helps prevent attacks like Cross-Site Scripting (XSS) and template injection.

Dangers of insecure implementations

Ignoring these security guidelines can lead to serious security issues, including:

  • Cross-Site Scripting (XSS): Malicious scripts can be executed in the user's browser, leading to data theft, identity theft, or account takeover.
  • Template Injection: Malicious users may try to inject unwanted code into templates, leading to the execution of harmful scripts on the server.
  • Data Leakage: Insufficiently secured templates can accidentally expose sensitive data, leading to data breaches.

Best practices summarized

  • Always use the |escape modifier to sanitize output.
  • Validate and clean all input data to ensure it doesn't contain harmful content.
  • Work with trusted data sources and avoid direct user input without validation.

By following these best practices, you can safely and effectively utilize the powerful personalization capabilities of Smarty. This way, you protect not only your organization but also your customers while providing them with a personalized and engaging experience.