During a recent Google SEO Office Hours session, a query arose regarding the potential impact of security headers on search rankings. The question holds significance due to the role played by security headers, such as the HSTS header, in ensuring a secure HTTPS connection. It is worth noting that HTTPS serves as a lightweight ranking signal for Google, further emphasizing the relevance of this inquiry.
HSTS Security Header
A header is a server response to a browser or a crawler. The most well-known header is the response header, like the 404 Error Response or the 301 response header. The purpose of an HTTP header is to offer additional metadata about the webpage that a browser or crawler is requesting. Security headers are a particular group that enforces different kinds of security to protect against various malicious attacks and keep the site secure for users.
An HSTS security header is a response that tells the browser that the webpage should only be accessed via HTTPS, never by HTTP, and to request HTTPS the next time.
The HSTS (HTTP Strict Transport Security) security header is an essential mechanism used to enhance the security of websites and protect against certain types of attacks. An HTTP response header instructs web browsers to only communicate with the website over secure HTTPS connections, thereby enforcing secure communication between the client and the server.
The primary purpose of the HSTS security header is to prevent man-in-the-middle attacks, where an attacker intercepts and modifies communication between a user’s browser and a website. By specifying the HSTS header, websites can ensure that all subsequent requests to their domain are automatically directed to HTTPS, even if the user initially enters the URL with the HTTP protocol.
When a web browser receives an HSTS header from a website, it remembers the directive for a specified period and enforces HTTPS for subsequent visits to that domain. This helps to eliminate the risk of downgrading attacks, where an attacker attempts to force the use of insecure HTTP connections.
Implementing the HSTS security header significantly improves the overall security posture of a website and protects users from various security vulnerabilities. Enforcing HTTPS ensures that sensitive information, such as login credentials or personal data, is transmitted securely, reducing the risk of eavesdropping and data interception.
It is important to note that once the HSTS header is set for a domain, it also applies to all subdomains. Additionally, the HSTS preload list, maintained by browser vendors, can include a website in a preloaded list of HSTS-enabled websites. It ensures that even users visiting the website for the first time will automatically be redirected to HTTPS.
In conclusion, the HSTS security header is a crucial security mechanism that helps protect websites and users by enforcing secure HTTPS connections. It mitigates the risk of man-in-the-middle attacks and ensures that sensitive information is transmitted securely over the internet. Implementing HSTS is a recommended practice for website administrators and developers seeking to enhance the security of their online platforms.
Does the HSTS Header Influence Rankings?
Here is the question asked to John Mueller:
“Does the integration of security headers such as for HSTS have a ranking influence?”
John Mueller Replied:
“No, the HSTS header does not affect Search. This header is used to tell users to access the HTTPS version directly and is commonly used together with redirects to the HTTPS versions.
Google uses a process called canonicalization to pick the most appropriate version of a page to crawl and index—it does not rely on headers like those used for HSTS. Using these headers is of course great for users though.”
Can HSTS be a Good Security Practice?
According to John Mueller, Googlebot does not depend on headers, but HSTS serves as communication to browsers. Nonetheless, it is crucial for every website to implement profitable security practices, irrespective of their impact on rankings. Chrome incorporates an HSTS preload list that all browsers utilize to automatically enable HTTPS since it is hardcoded into the browser. You can check the instructions for how to do it on the HSTS Preload website.
Listen to the Office Hours discussion at the 4:57 minute mark.