论文标题
海报：DNSSEC算法敏捷性的意外后果
Poster: The Unintended Consequences of Algorithm Agility in DNSSEC
论文作者
论文摘要
加密算法敏捷性是DNSSEC的重要属性：如果现有算法不再安全，则可以轻松部署新算法。在这项工作中，我们表明，DNSSEC的加密敏捷性虽然对于用强密码学配置DNS至关重要，但也引入了脆弱性。我们发现，在某些条件下，当在签名的DNS响应中列出新算法时，解析器不验证DNSSEC。结果，部署新密码的域实际上可能导致解析器不验证DNSSEC。我们利用这一点来开发DNSSEC-DOWNGRADE攻击，并在实验和道德上对其进行实验和道德评估，以针对全球网络客户使用的流行DNS解析器实现，公共DNS提供商和DNS服务。我们发现，网络客户使用的主要DNS提供商以及45％的DNS解析器容易受到我们的攻击。
Cryptographic algorithm agility is an important property for DNSSEC: it allows easy deployment of new algorithms if the existing ones are no longer secure. In this work we show that the cryptographic agility in DNSSEC, although critical for provisioning DNS with strong cryptography, also introduces a vulnerability. We find that under certain conditions, when new algorithms are listed in signed DNS responses, the resolvers do not validate DNSSEC. As a result, domains that deploy new ciphers may in fact cause the resolvers not to validate DNSSEC. We exploit this to develop DNSSEC-downgrade attacks and experimentally and ethically evaluate them against popular DNS resolver implementations, public DNS providers, and DNS services used by web clients worldwide. We find that major DNS providers as well as 45% of DNS resolvers used by web clients are vulnerable to our attacks.
