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Gerald Doussot - State of DNS Rebinding Attacks & Singularity of Origin

Gerald Doussot

Revives DNS rebinding as a practical attack against internal services and introduces the Singularity toolkit for automated exploitation.

Summary

DNS Rebinding: Resurrected and Weaponized

Gerald Doussot presents updated DNS rebinding attack techniques and introduces Singularity of Origin, an open-source toolkit for automating DNS rebinding attacks against internal services.

The Attack Mechanism

DNS rebinding abuses the same-origin policy (SOP) by first pointing a domain at the attacker's server, delivering malicious JavaScript, then rapidly changing the DNS record to point at an internal IP. The victim's browser then sends XHR requests to the internal target, believing it's still on the attacker's origin.

Modern Browser Defenses and Bypasses

Browser vendors have attempted mitigations including DNS TTL pinning. Doussot demonstrates that many browsers still honor rebinding with TTLs as low as 0, and provides race-condition techniques to beat TTL-based protections.

Singularity Toolkit

The open-source Singularity tool automates the DNS server, payload delivery, and rebinding timing to attack routers, smart home devices, Kubernetes dashboards, and other internal web services exposed on RFC-1918 addresses.

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