Bug 305466 – CSP Hash reports are sent for style assets when they should not be.

• Component: Page Loading
• Status: RESOLVED FIXED

[Scott Helme]

Created attachment 478014 [details]
CSP Hash reports being sent for styles but reported as scripts.

On our site, https://report-uri.com, we have the following CSP header:

    content-security-policy:
    default-src 'none';
    script-src cdn.report-uri.com 'nonce-*snip*' static.cloudflareinsights.com 'report-sha256' 'report-sample';
    style-src 'self' 'unsafe-inline' cdn.report-uri.com;
    img-src 'self' data: cdn.report-uri.com;
    font-src 'self' cdn.report-uri.com;
    frame-src 'self';
    frame-ancestors 'none';
    form-action 'self';
    connect-src 'self';
    upgrade-insecure-requests;
    base-uri 'none';
    report-uri https://helios.report-uri.com/r/t/csp/enforce;
    report-to default


It is using the 'report-sha256' keyword in the script-src directive, so we are expecting csp-hash reports to be sent for script assets. We have now started receiving csp-hash reports for style assets, with the destination value still set to script, from Safari browser:

    {
        "csp-hash": {
            "documentURL": "https://report-uri.com/",
            "subresourceURL": "https://cdn.report-uri.com/css/refresh/bootstrap.min.css",
            "hash": "sha256-7ZWbZUAi97rkirk4DcEp4GWDPkWpRMcNaEyXGsNXjLg=",
            "type": "subresource",
            "destination": "script"
        }
    }


The main bug I believe is that these should not be sent, as we are not requesting csp-hash reports for style assets, but also if they were to be sent, the destination value needs to be updated to correctly reflect style.

[Yoav Weiss]

Pull request: https://github.com/WebKit/WebKit/pull/56624

[Radar WebKit Bug Importer]

<rdar://problem/168575888>

[EWS]

Committed 305935@main (af444252a020): <https://commits.webkit.org/305935@main>

Reviewed commits have been landed. Closing PR #56624 and removing active labels.