黑帽大会2023(欧洲)

摘要

In this paper, we present a new DNS amplification attack, named TsuKing. Instead of exploiting individual DNS resolvers independently to achieve an amplification effect, TsuKing deftly coordinates numerous vulnerable DNS resolvers and crafted queries together to form potent DoS amplifiers. We demonstrate that with TsuKing, an initial small amplification factor can increase exponentially through the internal layers of coordinated amplifiers, resulting in an extremely powerful amplification attack. TsuKing has three variants, including DNSRetry, DNSChain, and DNSLoop, all of which exploit a suite of inconsistent DNS implementations to achieve enormous amplification effect. With comprehensive measurements, we found that about 14.5% of 1.3M open DNS resolvers are potentially vulnerable to TsuKing. Real-world controlled evaluations indicated that attackers can achieve a packet amplification factor of at least 3,700× (DNSChain). We have reported vulnerabilities to affected vendors and provided them with mitigation recommendations. We have received positive responses from 6 vendors, including Unbound, MikroTik, and AliDNS, and 3 CVEs were assigned. Some of them are implementing our recommendations.

日期
12月 6, 2023 12:00 AM — 11:59 PM
位置
EXCEL LONDON
One Western Gateway, London, E16 1XL

在黑帽大会2023(欧洲)上, 段海新教授分享了我们的研究工作:“TsuKing: Coordinating DNS Resolvers and Queries into Potent DoS Amplifiers”。

李想
李想
清华大学博士研究生(网络空间安全)

李想,清华大学网络科学与网络空间研究院五年级博士研究生,导师为李琦副教授和段海新教授。研究方向为网络与协议安全,已发表论文18篇(含一作6篇:在网络安全四大顶会均有发表、通讯1篇、二作3篇),第一发明人授权专利1项及实质审查中5项(共11项),在Black Hat多次分享,获得200+CVE等漏洞编号,330+GitHub stars。研究获得多个政府及大学CERT安全公告、100+媒体报道,并被纳入RFC标准文档。其也获得了多项奖项荣誉,如IPv6创新大赛一等奖、GeekCon国际安全极客大赛亚军及非凡黑客荣誉称号、王大中奖学金、博士研究生国家奖学金、清华优秀奖学金等。