The policy allows resources from anywhere

LowConfirmedweb.security-headers.csp-wildcard-source

What this check looks for

Part of the policy uses a wildcard, which permits any address at all. That directive restricts nothing.

Why it matters

A policy is only as strong as its loosest directive. A wildcard in one place often makes the careful work done everywhere else irrelevant.

When the check passes, your report says: “Every source in the policy names a specific origin”.

What it costs your score

When this check fails it removes 6 points from your Web security score, before the status, confidence and repeat multipliers are applied. Web security carries a weight of 8 in the overall score.

It shares the web-security.csp family ceiling of 30 points: however many findings that family produces, together they cannot remove more than that from Web security. One underlying problem showing up in several places is still one problem.

Severity: low
Default confidence: confirmed
Status when triggered: warn
Deduction: 6 points
Family cap: web-security.csp · 30
Category: Web security
Module: Web security headers
Fix owned by: user
In the ruleset since: 2026.09

How the whole score is calculated

How to fix it

Replace each wildcard with the specific origins the page actually uses.

One wildcard directive can undo the whole policy.

Use report-only mode to collect the origins the page really loads from.
List those origins explicitly.
For scripts, prefer a nonce with 'strict-dynamic' — it removes the allow-list entirely.

How to confirm it worked

curl -sSI https://‹host›/ | grep -i content-security-policy

A named slot like ‹domain› — and the braces left in the configuration below — is filled in with your own values when this rule appears on a report.

Remediation by platform

nginx

add_header Content-Security-Policy "default-src 'self'; img-src 'self' data:" always;

Apache

<IfModule mod_headers.c>
	Header always set Content-Security-Policy "default-src 'self'; img-src 'self' data:"
</IfModule>

Caddy

header {
	Content-Security-Policy "default-src 'self'; img-src 'self' data:"
}

Cloudflare

Rules → Overview → Create rule → Response Header Transform Rule → Set static → Content-Security-Policy = default-src 'self'; img-src 'self' data:
(Dashboard path as at 2026-09; Cloudflare reorganised these pages and may again.)

The always flag matters: without it nginx omits the header on error responses, which are exactly the ones an attacker aims for. Note also that any add_header in a location block discards every add_header inherited from the server block.
Shown because the response identified Apache. Put it in the virtual host rather than .htaccess: .htaccess is re-read on every request, and Header always set there runs too late for responses the server generates itself.
A Transform Rule adds the header at Cloudflare's edge, so it applies only to responses that reach visitors through Cloudflare. An origin that is reachable directly — by IP, or through a DNS record that is not proxied — still serves the response measured here without it. Setting it at the origin covers both paths.

Technical detail

These directives permit *, http:, https:, data: or blob:: ‹directives›.

data: deserves a special mention — in script-src or object-src it lets an attacker inline an entire payload as a URL, so it defeats the directive completely. A wildcard in img-src is a much smaller matter than one in script-src, and the report names the directive so the difference is visible.