Re: DNS query spam

[Florian Weimer <fw () deneb enyo de>]

* Josep Ma Castells:

> I have the same problem, now I'm blocking this attempts with iptables and 
> the Recent module when a number of tries is reached.
>
> This is the content of the packet:
> =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
>
> 11/20/05-19:17:37.177173 168.143.XXX.XX:11752 -> YYY.YYY.Y.YY:53
> UDP TTL:233 TOS:0x0 ID:34960 IpLen:20 DgmLen:68 DF
> Len: 48
> 0x0000: 00 07 95 C2 6A 32 00 04 76 DA CB 14 08 00 45 00  ....j2..v.....E.
> 0x0010: 00 44 88 90 40 00 E9 11 2A D5 A8 8F 71 0A C0 A8  .D..@...*...q...
> 0x0020: 04 01 2D E8 00 35 00 30 00 00 20 9E 01 00 00 01  ..-..5.0.. .....
> 0x0030: 00 00 00 00 00 01 01 65 05 6D 70 69 73 69 03 63  .......e.mpisi.c
> 0x0040: 6F 6D 00 00 FF 00 FF 00 00 29 27 10 00 00 00 00  om.......)'.....
> 0x0050: 00 00                                            ..
>
> =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+

Interesting.  This packet allegedly came from www.anonymizer.com
(168.143.113.10).  It apparently has undergone NAT, so its contents
might have been garbled, but: In contrast to Piotr's packets, this one
does contain an OPT RR (type 0x29).  The sender buffer length (encoded
in the class field of the RR) is set to 10000.