> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/de/web/cors.md).

# CORS

CORS-Fehlkonfiguration, Origin-Reflexion, Vertrauen in Null-Origin, unsichere Protokolle und Cross-Origin-Credential-Diebstahl.

CORS-Notizen für PortSwigger Web Security Academy Labs, mit Schwerpunkt auf praktischen Testschritten, Burp-Suite-Validierung, Payload-Verhalten und Exploit-Workflow.

## Test-Workflow

1. Identifizieren Sie die verwundbare Funktion und die relevante Anfrage, den Parameter, den Header, das Cookie oder die sink auf der Browser-Seite.
2. Reproduzieren Sie das Verhalten in Burp Suite mit einem minimalen Payload, bevor Sie den Angriff ausweiten.
3. Validieren Sie die Auswirkung mit einem klaren Proof of Concept, wie etwa Kontozugriff, Datenpreisgabe, Codeausführung, SSRF oder Statusänderung.
4. Behalten Sie Payloads, URLs, Tokens und Lab-Zugangsdaten unverändert, während Sie den Ausnutzungspfad dokumentieren.

## Labs

<table><thead><tr><th data-type="content-ref"></th></tr></thead><tbody><tr><td><a href="/de/web/cors/cors-basic-origin-reflection.md">Einfache CORS-Origin-Reflexion</a></td></tr><tr><td><a href="/de/web/cors/cors-null-origin-trusted.md">Vertrauenswürdige Null-Origin bei CORS</a></td></tr><tr><td><a href="/de/web/cors/cors-with-trusted-insecure-protocols.md">CORS mit vertrauenswürdigen unsicheren Protokollen</a></td></tr></tbody></table>


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