Damn, damn, damn

[brixtonbrood]

In amongst the spam (Demon's filter has been distinctly falling behind in its Red Queen's Race of late) we've just received seven non-receipt notifications to e-mails we never (knowingly) sent with addresses that don't exist.
I assume that this means that our computer is an evil zombie spam-monster, heaven knows how it got infected. Does anyone know what we should do next? (thinks: this is why I don't do online banking).

Comments

[swisstone.livejournal.com]

It doesn't necessarily mean that your machine is infected. It could just be that your address has been spoofed. I've had that happen to me, and every time it does I run all the latests spyware and AV checks, and I never find anything.

[brixtonbrood.livejournal.com]

Thanks, touch wood it seems to be calming down now.

[tea-and-cuddles.livejournal.com]

I have received up to 5000 non-receipt notifications per day, and they are not caused by spam from my computer - they are due to emails purporting to be from my address, or other addresses at my domain, but sent from elsewhere. It's called spam backscatter, and is sometimes more of a problem than spam itself.

[brixtonbrood.livejournal.com]

Thanks for reassurance, it seems to have calmed down a bit now.

[truecatachresis.livejournal.com]

What Jamie said, and to reinforce - don't worry about it too much. You aren't likely to get your email address blocked as a spammer, as all the blacklisters know about this.

It never hurts to be safe, though, so I'd recommend Windows Defender, Lavasoft AdAware, Spybot Search and Destroy and AVG Antivirus. All free, and it doesn't hurt to run them all. You probably won't find anything dangerous, you probably don't have anything nasty, but it's definitely worth checking every so often.

[brixtonbrood.livejournal.com]

I've run Adaware and found nothing except cookies.

[the-magician.livejournal.com]

Then I'm 99.9% sure it's not your machine sending those emails you're getting the NDN replies to (non-delivery notifications)

I get hundreds of them per day and have had to install MailWasher to clear them out of the server before I pull down my email ... in fact MailWasher(Pro) currently kills 77% of my email on the server, and flags up with a greater than 90% accuracy the rest of the spam ... so I just double check to make sure there are no false positives and hit the "delete all marked" button in mailwasher and it kills the rest of the spam on the server.

But then I'm averaging 1,000 emails a day, so being able to kill nearly 800 of them without looking is really useful!

[brixtonbrood.livejournal.com]

That's reassuring, although if I end up with hundreds of NDNs a day I'm still going to have to do something (probably involving chats to a charming young Irish man at Demon who will hold my hand).

[the-magician.livejournal.com]

Indeed.

It does seem to come in pulses .. I reckon they just take a chunk of domain names (perhaps off a spam list) and then send out 100s of thousands of messages from "alan@domain, bob@domain, charles@domain, sdf790sdd@domain" etc. to try to get past spam filters that have "domain" listed as a valid domain (business or friend) and obviously a large number of these are rejected. Annoyingly the mail gets rejected by servers that send back an NDN for each dud email (even if they get 10,000 different emails from the same "domain" and reject 9,998 of them, they then send 9,998 reject messages rather than just realising it's a spam flood, and so those 9,998 reject messages show up in your inbox ... sigh.

I get far more NDNs through than I get spam. (Or so I believe)

Good luck with the Demons