[nsp-sec] DNS amplification attack to 213.171.220.101

[Florian Weimer]

* Gerard White:

> Yup.  For practically every DNS speaking device I can find here,
> there's a continuous type 16 (Text Strings) Query for
> "johnmadness.com"...  Query ID's are unique and random.  oddly
> enough there's an additional record present in the queries - a Type
> 41 (Option) (Class 65535).

The OPT pseudo-RR enables clients to request larger UDP packets than
the default 512 bytes.  This way, you can achieve an amplification
factor between 70 and 80 in a reflective attack.

-- 
Florian Weimer                <fweimer at bfk.de>
BFK edv-consulting GmbH       http://www.bfk.de/
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