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Blessed BadDNS, Who Refused the Right Answers
Patron of DNS resolvers, predictable source ports, and answers discarded by mistake.
Life
In March 2023 researcher Xiang Li described BadDNS, a class of flaws in which a DNS resolver can be made to ignore legitimate responses, left without the answer it needed and so denying service. According to the author the effect could be wide, because sometimes it was enough to forge a packet toward the resolver's source port, without guessing the query's identifier.
Prayer
O Blessed BadDNS, who throws away the right letter while waiting for the false one, teach our resolvers to recognise who really answers. Amen.
How to celebrate
Celebrated by updating DNS software, randomising source ports, and validating every response with care.
Refuse the true answer, and you're left with none.