An HTTP response header that constrains which sources of scripts, styles, and other resources a browser will execute.
CSP is the strongest browser-side defence against XSS. Modern policies use strict-dynamic with a per-request nonce: only nonced inline scripts run, and dynamically inserted scripts inherit trust from their loader.
See our web application penetration testing, API security testing, network penetration testing, and cloud security audit services for how we test for and defend against this class of issue.
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