Weekly spam summary on May 13th, 2006
Unfortunately, the SMTP frontend died shortly after midnight on Tuesday morning, so some of the connection statistics are missing about 2.6 days. Given that, this week we:
- got 11,652 messages from 229 different IP addresses.
- handled 16,296 sessions from 808 different IP addresses.
- received 110,313 connections from at least 35,408 different IP addresses since early Tuesday morning.
- hit a highwater of 11 connections being checked at once since early Tuesday morning.
At the Monday morning volume timestamp, we had received 210,731 connections from at least 7,733 different IP addresses; from this I suspect that that spam storm from Saturday of last week continued full-bore on last Sunday.
Kernel level packet filtering top ten:
Host/Mask Packets Bytes 18.104.22.168 13422 644K 22.214.171.124/24 6112 305K 126.96.36.199 4554 273K 188.8.131.52/10 3484 173K 184.108.40.206 3397 163K 220.127.116.11/13 3047 151K 18.104.22.168/11 2692 137K 22.214.171.124/11 2358 118K 126.96.36.199 2309 117K 188.8.131.52 2132 99671
Overall, this is a bit more active than last week, but it's mostly driven up by a few people; there seems to have been no overall volume surge.
- 184.108.40.206 is a Hong Kong cablemodem, and was mentioned in passing last week.
- 220.127.116.11 is in the CBL. (And Canadian, alas.)
- 18.104.22.168 in in a Shaw Cable SPEWS listing. I've actually seen it in log summaries for previous weeks (although never high enough to get in this report), and it has a good looking DNS name, and it's not listed anywhere else, so I am going to whitelist it and see what happens.
- 22.214.171.124 is a covad.net 'dialup' machine.
- 126.96.36.199 returns from this April;
we consider it a dialup machine, and it's also in
bl.spamcop.netand the DSBL.
Connection time rejection stats:
40201 total 19942 dynamic IP 16960 bad or no reverse DNS 2033 class bl-cbl 233 class bl-spews 119 class bl-sdul 118 class bl-dsbl 83 class bl-sbl 49 class bl-ordb 19 class bl-njabl 3 class bl-opm
Although this looks down from last week, the details make Sunday's
spam storm pop out. All 30 of the top 30 most rejected IP addresses
were rejected more than 100 times; the most active one was our friend
188.8.131.52, with 619. 27 of the top 30 are currently in the CBL, 4
are currently in
bl.spamcop.net, and 184.108.40.206 (123 rejections) is
SBL39408 is one of those depressing SBL listings; it is for 220.127.116.11/15, which belongs to Vietnam Posts and Telecommunications Corp (VNN.VN). Created April 10th 2006, the two /16 halves of it are apparently the current worst and second worst /16 spam source networks on the Internet. Somehow I suspect that they are going to retain that status for a while.
Hotmail is doing much better this week:
- one message accepted.
- 4 messages rejected because they came from non-Hotmail email addresses (all from various non-US Hotmail domains; I really have to improve that check).
- no messages sent to spamtraps, refused because the sender had already hit spamtraps, or rejected because of their originating IP address.
I'm willing to tentatively declare that Hotmail has fixed their problem. Besides, as far as I can tell the problem free webmail provider is now Yahoo; I am getting significant advance fee fraud spam through Yahoo from a spam gang that they haven't stopped. (The situation is bad enough that I have started blocking non-US Yahoo operations as they spam us.)
The final numbers:
|what||# this week||(distinct IPs)||# last week||(distinct IPs)|
More than half (244 out of 448) of the bad
HELOs came from
btconnect.com's pool of SMTP senders in 18.104.22.168/24, which
with names like 'hesa05uker.he.local' (sometimes capitalized). The
pattern for usernames in the bad bounces is fairly similar to last
week, including another bounce to that 38-character hex sequence (but
from a different domain).