## The peculiar case of NSEC processing using expanded wildcard records

- 種別: release
- 関連技術: unbound, powerdns
- 公開日時: 2018-01-29T23:00:00.000Z
- 情報源: NLnet Labs (https://nlnetlabs.nl/news/2018/Jan/30/the-peculiar-case-of-nsec-processing-using-expanded-wildcard-records/)
- パーマリンク: https://vulnpulse.app/items/nlnetlabs-745b1c069e29

We discovered a vulnerability in the processing of wildcard synthesized NSEC records. The result was Unbound, Google public DNS, PowerDNS and Dnsmasq contained a flaw that made it possible to downgrade secure connections. While synthesis of NSEC records is allowed by RFC 4592 , these synthesized owner names should not be used in the NSEC processing. This does, however, happen in Unbound 1.6.7 and earlier versions. Ralph Dolmans wrote a blog post about the discovery and findings.