Date: November 9, 2021, 14:30-15:30 UTC Webex link: https://meetings.conf.meetecho.com/ietf112/?group=maprg&short=&item=1
IRTF Note-well: https://irtf.org/policies/irtf-note-well-2019-11.pdf
The Internet’s Domain Name System (DNS) is a part of every web request and e-mail exchange, so DNS failures can be catastrophic, taking out major websites and services. This paper identifies TsuNAME, a vulnerability where some recursive resolvers can greatly amplify queries, potentially resulting in a denial-of-service to DNS services. TsuNAME is caused by cyclical dependencies in DNS records. A recursive resolver repeatedly follows these cycles, coupled with insufficient caching and application-level retries greatly amplify an initial query, stressing authoritative servers. Although issues with cyclic dependencies are not new, the scale of amplification has not previously been understood. We document real-world events in .nz (a country-level domain), where two misconfigured domains resulted in a 50% increase on overall traffic. We reproduce and document root causes of this event through experiments, and demostrate a 500× amplification factor. In response to our disclosure, several DNS software vendors have documented their mitigations, including Google public DNS and Cisco OpenDNS. For operators of authoritative DNS services we have developed and released CycleHunter, an open-source tool that detects cyclic dependencies and prevents attacks. We use CycleHunter to evaluate roughly 184 million domain names in 7 large, top-level domains (TLDs), finding 44 cyclic dependent NS records used by 1.4k domain names. The TsuNAME vulnerability is weaponizable, since an adversary can easily create cycles to attack the infrastructure of a parent domains. Documenting this threat and its solutions is an important step to ensuring it is fully addressed.
VPN are a secured tunnel that help service providers to exchange data over non-secured networks. There is a large variety of VPN solutions that have variable deployment impacts on the target architecture as well as performance limitations or opportunities. This technical report compares Wireguard and OpenVPN for various SATCOM deployment scenarios and topologies.
Consumer IoT devices are becoming increasingly popular, with most leveraging TLS to provide connection security. In this work, we study a large number of TLS-enabled consumer IoT devices to shed light on how effectively they use TLS, in terms of establishing secure connections and correctly validating certificates, and how observed behavior changes over time. To this end, we gather more than two years of TLS network traffic from IoT devices, conduct active probing to test for vulnerabilities, and develop a novel blackbox technique for exploring the trusted root stores in IoT devices by exploiting a side-channel through TLS Alert Messages. We find a wide range of behaviors across devices, with some adopting best security practices but most being vulnerable in one or more of the following ways: use of old/insecure protocol versions and/or ciphersuites, lack of certificate validation, and poor maintenance of root stores. Specifically, we find that at least 8 IoT devices still include distrusted certificates in their root stores, 11/32 devices are vulnerable to TLS interception attacks, and that many devices fail to adopt modern protocol features over time. Our findings motivate the need for IoT manufacturers to audit, upgrade, and maintain their devices’ TLS implementations in a consistent and uniform way that safeguards all of their network traffic.