Cookie Security Checker
Inspect the cookies a website sets and check Secure, HttpOnly, SameSite and cookie-prefix hygiene.
About Cookie Security Checker
Every cookie without Secure, HttpOnly or a proper SameSite is one XSS or CSRF away from a session hijack — and a growing pile of privacy laws now hinge on knowing exactly what you set. This checker inspects the raw Set-Cookie response and grades each attribute against the current OWASP and browser recommendations.
What this tool checks
Cookie Security Checker focuses on the following signals from your site's live response:
cookiesmodule in the full audit
Why it matters
Signals covered by Cookie Security Checker are the ones attackers, browsers, and search engines look at first. A weak result here means real users are exposed — via downgrade attacks, broken trust warnings, indexing problems, or leaked data — long before anything obvious breaks. Fixing them is usually a config change, not a rewrite, and the impact is immediate.
How to interpret your result
- Pass — the signal meets modern best practice. Keep it monitored; regressions happen after deploys.
- Warn — functional but weaker than recommended. Usually a quick header, DNS, or config tweak away from a full pass.
- Fail — a real risk to users or search visibility. Follow the recommendation shown next to the finding — it's copy-pasteable.
Best practices
- • Re-run after every deploy — configuration drift is the #1 cause of regressions.
- • Compare against a competitor's report to spot easy wins.
- • Wire the public API into CI to gate merges on the score.
- • Fix warns before failures — they're the cheapest to close and pay off compounding gains.
Frequently asked questions
Related guides
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