Is more Spam getting through Thunderbird's Junk Filter lately?

October 18, 2005 8:17 AM

Is more Spam getting through Thunderbird's Junk Filter lately?

For a few of days now I'm getting 10 - 15 spam emails per hour that are not being caught by Thunderbird's Adaptive Junk filter. Is there some new Spam method being used here?

posted by Cookiebastard to computers & internet (12 comments total)

I've been using Thunderbird for about a year now. Up until the last month or so, zero junk got through it, but now I'm getting about two or three a week. Nothing to complain about for sure, but yeah, junk is starting to seep through. I don't really post that particular email address anywhere on the interweb though, so that would account for such little junk mail, but still, it seems strange that anything would get in.
posted by NoMich at 8:24 AM on October 18, 2005

Have you updated your version of Thunderbird recently?
I get, probably, about 50 pieces of junkmail every day and Thunderbird fails to screen out about one piece for every two days that go by.
Just make sure that you consistantly "mark as junk" the undesired mail, rather than deleting it. It's how Thunderbird adapts.
posted by Jon-o at 8:32 AM on October 18, 2005

I'm not sure if I'm just making this up, or what. But it always seems like the Thunderbird mail filter stops working as wel after a while. As in when I first install thunderbird, it of course isn't very good, then it gets awesome, then it gets terrible again. If I reinstall thunderbird, the same thing happens.

Or maybe I'm just crazy.
posted by KirTakat at 8:33 AM on October 18, 2005

I've noticed the same thing. To my eye, the junk mail that's getting through uses three random couplets from poetry or some other source. Such as:

Oh, what lies there are in kisses!
Abstinence is as easy to me, as temperance would be difficult.

There is no great concurrence between learning and wisdom
You can't truthfully explain your smallest action without fully revealing your character.

Do not speak ill of the dead.
Doing a thing well is often a waste of time.

I assume that if they can keep mixing up those random lines well enough, and the ad part short enough, it may be unlikely to score enough enough for Thunderbird--or perhaps most filters--to catch it.
posted by skynxnex at 8:37 AM on October 18, 2005

The existence of junk filters simply accelerates the evolution of spam. Think about it. When improved filtering becomes available, spammers are forced to tweak their messages to get through them. Filters help them make better spam. There's a lag between filters and the "improved" spam, but it's getting shorter. It's an arms race.
posted by ldenneau at 8:51 AM on October 18, 2005

I don't use Thunderbird, but for what it's worth, I have noticed an increase in spam in Apple Mail during the past month. I used to rarely have spam make it to my inbox, but lately I'm getting three or four junk messages a day that don't get routed to my junk mail folder. I know this doesn't answer your question, but maybe the problem isn't on your end.
posted by lewistate at 8:53 AM on October 18, 2005

My Apple Mail filter went through a similar rapid decline in the last couple weeks.
posted by mkultra at 8:53 AM on October 18, 2005

My Apple Mail filter did the same thing, but since I use JunkMatcher, too, it's all been caught. (Also, incidentally, Pair.com recently turned on more advanced filtering on my mail server--greylisting alone has cut my spam by 80 percent.)
posted by Mo Nickels at 9:14 AM on October 18, 2005

Is it a bayenesian (?) filter? I use Spambayes Outlook plugin and have also noticed a bit more spam being missed than normal..
posted by jeffmik at 9:15 AM on October 18, 2005

Just reset your filter (Tools -> Junk Mail Controls -> Adaptive Filter -> Reset Training Data).

Your filter is trained to catch last year's spam. Reset the filter, train it quick-like on the last 100 or so spams you got and a bunch of non-spam, and notice an immediate improvement. I too have been getting 5-10 spam per day make it through the filter, but after resetting it last night, I've had none.
posted by gleuschk at 10:29 AM on October 18, 2005

I never found Thunderbird's junk detector very effective. Mail + JunkMatcher has worked very well almost out of the box.
posted by yerfatma at 10:30 AM on October 18, 2005

Yes, jeffmik, Junk Mail Controls is a Bayesian filter. That page includes a link to an extension that allows you to manage the training data.

One thing that happens is that mistakes build up over time, which raises the false positive (where positive = identified as spam) rate. Some folks advocate resetting your controls when this happens.

I find JMC adequate, but it's a basic tool intended to enhance the value of the Thunderbird product. There's no reason you can't use a better one.

Filters help them make better spam.

That's misstated. Filters force them to make better spam. So do other enforcement and mitigation methods.

Incidentally, Thunderbird 1.5 -- now in beta -- will include a phishing detector and server-side spam filter integration.
posted by dhartung at 12:20 AM on October 19, 2005