Virus and Spam Storms

Caught an interesting little thing in my mail logs the other day. Take note of the two sudden and sustained peaks. The graph shows incoming SMTP connections. Now the next graph shows messages delivered. The increased number of incoming SMTP connections seems to have no impact on the number of... [Read article]

The Cost of Spam

The amount of spam e-mail is ever increasing. The cure for spam is not simple, but there are quite some measures that could be taken on a ISP level to limit the effectiveness of spam. Little or nothing is done, often ISPs charge for spam-filtering services, and often the services... [Read article]

K9 Spam-Filtering Software

Some weeks ago, after once again discarding a useless piece of Spam-Filtering software for Outlook I found and article about K9 in a local newspaper online. After having used it for about two weeks I am ready to say that K9 is the best spam-filtering software I have seen for... [Read article]

Spam Developments

Just took a look in my spam folder the other day. I do that every so often to see if I have any false positives that I would like to read. Anyways; pretty quickly I realized that the appearance of spam has changed rather a lot lately. In 'previous times'... [Read article]

MSN Messenger Spam

In Yahoo! Messenger Spam I complained about spam messages sent to my Y! Messenger account. Now that activity stopped, but now it is my MSN Messenger that keeps pouring in with spam... time to turn on the BLOCK: all other option...... [Read article]

SpamAssassin Score Record

Some week ago I installed SpamAssassin 2.41, and made sure that all the necessary Perl modules were properly installed, to get the most out of SA. Instantly after installing the amount of spam leaking through SA was reduced (which was not really that surprising). Just now I looked through the... [Read article]

Statistical Analysis of Spam - Part IV

My series on spam and the statistical aspects behind it continues. Last time (part III) I discovered that the probability distribution of spam seemingly was Weibull. An interesting discovery. Add to this some knowledge about the Weibull distribution, and some results from Minitab and one suddenly can actually calculate the... [Read article]

Statistical Analysis of Spam - Part III

Once more it is time to study the statistical aspects of spam. In part II I commented on the differences in two independent sets of spam. Today I will try to be slightly more scientific. Just by looking at the histograms in the previous posting it is easy to see... [Read article]

Yahoo! Messenger Spam

These days it ain't only by e-mail one recieves spam. Lately my Yahoo! Messenger account seems to recieve a more than normal amount of 'spam' messages. Todays last message (and what made me write this post) came in as: pamela_21_px: hello, here's my pic, http://64.38.228.85/pamela/ wanna chat? or call me?... [Read article]

Statistical Analysis of Spam - Part II

Just after finishing my last piece on this topic (Statistical Analysis of Spam - Part I) I recieved a list of some 1900 X-Spam-Status lines from Anders. Inserting this into Minitab I expected to get two graphs looking more or less similar to eachother. No such luck. The graph below... [Read article]

Statistical Analysis of Spam - Part I

As Anders pointed out earlier today I have been working on analysing spam statistically. I made a brief introduction to it in Spam Filtering - To Do or Not To Do, and this is the first results emerging. I have been using Minitab to analyse the results gathered from my... [Read article]

Spam Filtering - To Do or Not To Do

Spam has become an increasing problem. There are many ways of fighting spam. Relay blacklists and filtering out e-mail without the correct To: header was the first generation of spam filtering. Seldom was it very successfull, atleast not for me. The blacklists took some, and some very naïve filtering rules... [Read article]