DeepSec 2022 Talk: Melting the DNS Iceberg – Taking Over Your Infrastructure Kaminsky Style – Dipl.-Ing. Timo Longin BSc

Sanna/ September 7, 2022/ Conference

What does DNS have in common with an iceberg? Both are hiding invisible dangers! Beneath an iceberg there is… even more ice. However, beneath the DNS there are hiding unexpected vulnerabilities! If you want to resolve a name via DNS, there are multiple open DNS resolvers all across the Internet. A commonly used open DNS resolver is Google’s resolver with the IP address 8.8.8.8. However, not every system is using such an open resolver. Hosting providers, ISPs and the like, are often using resolvers that are not directly accessible from the Internet. These are the so called “closed” resolvers. In my previous research “Forgot password? Taking over user accounts Kaminsky style,” I have unearthed critical vulnerabilities in DNS resolvers of web applications, but I haven’t shared a second thought about the fact that these

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DeepSec 2018 Talk: DNS Exfiltration and Out-of-Band Attacks – Nitesh Shilpkar

Sanna/ August 27, 2018/ Conference, Security

“The Domain Name System or DNS is one of the most fundamental parts of the Internet”, says Nitesh Shipkar. “It is crucial for a billion of users daily to help us build presence on the internet using names humans can understand rather than IP addresses. However, DNS comes with security issues organizations should be aware of and take into consideration. Attackers are abusing the DNS to redirect traffic to malicious sites, communicate with command and control (C&C) servers, steal data from organizations and conduct massive attacks that cause harm to organizations. Many organizations are not prepared to mitigate, or even detect, the problems DNS might bring. Due to the criticality of DNS to maintain an Internet presence, access applications, connect to a network or simply send an email, everyone has the potential to be

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DeepSec2016 Talk: Behavioral Analysis from DNS and Network Traffic – Josh Pyorre

Sanna/ October 4, 2016/ Conference, Internet, Security

What’s in a name? A rose? The preparation for an attack? Or simply your next web page you will be looking at? The Domain Name System (DNS) has gone a long way from replacing text lists of hosts to a full directory service transporting all kinds of queries. DNS even features a security protocol for cryptographically signed zone data. In order to balance the load, name resolution has caches that temporarily store DNS information. Usually organisations run their own DNS resolvers as caches for their infrastructure. Even if it’s just a flat network with local clients all DNS requests are channelled to hit your resolvers. Before applications open a data connection, they will query the local resolver to get address data or other hints on how to contact the other endpoint of the communication.

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