https://nalar.dev/tags/network-boundaries/ Recent content in Network Boundaries on Nalar Hugo en-us Sat, 19 Sep 2026 00:00:00 +0000 https://nalar.dev/dns-rebinding-preserves-web-origin-while-the-network-destination-changes/ Sat, 19 Sep 2026 00:00:00 +0000 https://nalar.dev/dns-rebinding-preserves-web-origin-while-the-network-destination-changes/ <h1 id="dns-rebinding-preserves-web-origin-while-the-network-destination-changes">DNS Rebinding Preserves Web Origin While the Network Destination Changes</h1> <p>A browser can treat two requests as same-origin even when the TCP connections behind them terminate at different IP addresses. The origin model is built from the URL scheme, host, and port. DNS resolution is a network operation beneath that identity. If a hostname resolves to one address and later resolves to another, the browser-facing origin can remain unchanged.</p> <p>DNS rebinding exploits that separation. An attacker-controlled hostname can initially resolve to an attacker-controlled server that delivers script, then later resolve to an address reachable from the victim&rsquo;s network. Subject to browser, resolver, transport, and target-service behavior, subsequent requests for the same hostname can then cross a network boundary without becoming cross-origin in the browser&rsquo;s origin model.</p>