Cookie missing SameSite attribute: what it is, why it matters, and how to fix it
One or more cookies are set without the SameSite attribute, making them potentially vulnerable to cross-site request forgery (CSRF) attacks.
Where this fits: security in SEO
Why cookie missing samesite attribute hurts your rankings
Without SameSite, cookies are sent with all cross-site requests by default, enabling CSRF attacks where malicious sites can make authenticated requests on behalf of the user. Modern browsers default to SameSite=Lax, but explicit declaration is recommended for clarity and compatibility.
This is a medium-severity issue: individually modest, but it compounds — dozens of medium issues across hundreds of pages add up to a real quality deficit in how search engines assess the site.
How to fix it
Add SameSite=Strict or SameSite=Lax to all cookies. Use Strict for cookies that should never be sent cross-site, and Lax for cookies that need to be sent on top-level navigations.
Set-Cookie: sessionId=abc123; Secure; HttpOnly; SameSite=StrictFrequently asked questions
What does "Cookie missing SameSite attribute" mean?
One or more cookies are set without the SameSite attribute, making them potentially vulnerable to cross-site request forgery (CSRF) attacks.
Why does cookie missing samesite attribute matter for SEO?
Without SameSite, cookies are sent with all cross-site requests by default, enabling CSRF attacks where malicious sites can make authenticated requests on behalf of the user. Modern browsers default to SameSite=Lax, but explicit declaration is recommended for clarity and compatibility.
How do I fix cookie missing samesite attribute?
Add SameSite=Strict or SameSite=Lax to all cookies. Use Strict for cookies that should never be sent cross-site, and Lax for cookies that need to be sent on top-level navigations.
How serious is this issue?
This is a medium-severity issue: individually modest, but it compounds — dozens of medium issues across hundreds of pages add up to a real quality deficit in how search engines assess the site. It belongs to the security family of checks.
How do I find every page affected by this on my site?
Run a free Dr Urls audit: it crawls your site, detects cookie missing samesite attribute on every affected page, shows example URLs, and generates a ready-to-use fix task. Re-scan after fixing to verify the issue is gone.
Does your site have this issue?
A free Dr Urls audit crawls your site, finds every page affected by cookie missing samesite attribute, and hands you a ready-made fix task.
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