A short HSTS max-age leaves a window in which a downgrade attack still works, and preload list submission requires 31536000 or more.
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How this rule is weighted
- Importance
- 5 / 10
- How much this matters relative to other rules.
- Confidence
- SPECIFICATION
- A standard says so: HTML, WCAG, an RFC or Google's own documentation.
- Severity
- warning
- How the finding is presented when it fails.
- Scoring
- Counts
- A failure costs points in its category.
Impact is importance multiplied by the confidence tier’s weight — SPECIFICATION 1.0, RESEARCH 0.7, EMERGING 0.3, EXPERIMENTAL 0.1. Two rules backed by the same class of evidence therefore always carry the same weight, which is what makes the score reproducible rather than hand-tuned.
Questions about this rule
- Does SEC_HSTS_LONG_MAXAGE affect my score?
- Yes. It is an importance 5 rule at SPECIFICATION confidence, so a failure costs 5 × 1 points of impact in the Security category before that category is normalised to 100.
- What does SPECIFICATION confidence mean?
- A standard says so: HTML, WCAG, an RFC or Google's own documentation. Confidence is a declared tier rather than a per-rule number, so every rule backed by the same class of evidence carries the same weight - which is what makes the score reproducible instead of hand-tuned.
- How do I check SEC_HSTS_LONG_MAXAGE on my own site?
- Paste your URL into the box above and it runs only this rule, usually in a couple of seconds. It is also included in the Security checker and in a full scan.
Tags
- security
- https
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