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I think my MacBook Pro might be hacked. The reason I found out about the website is because I did a netstat search in Terminal. My browser was closed but nevertheless it showed this:

tcp4       0      0  macintosh.lan.50419  LAST_ACK

among other things. I have never visited this website in my life.

Also netstat results show things that I think might be not right. Also I have been trying to figure this out for the past hours and recently (maybe 20 minutes ago) my screen went black for like a second or two and this never happens.

Anybody know whats wrong?

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migrated from Feb 5 '11 at 16:54

This question came from our site for professional and enthusiast programmers.

Have you tried Anti-Virus software (yes, there's software like that for Mac, too)? – andre_roesti Feb 5 '11 at 16:53
thank you for your answer but the strange thing i have never visited this website in my life I am certain of that and it didnt show up on an earlier netstat search – user66222 Feb 5 '11 at 17:00
@Worried - your question was posted on Stack Overflow, here, and was migrated here because it was off-topic on SO. You might not have visited this site before, but you've visited a site in the network before. – DMA57361 Feb 5 '11 at 17:01
it doesn´t matter if it is truncated it now shows the same results in netstat with the .co – user66222 Feb 5 '11 at 17:16
@oKtosiTe, the truncated "fixed column width" is far more obvious when not seeing just a single line of the output. – Arjan Feb 5 '11 at 18:01

LAST_ACK simply means that a connection to the specified server was recently closed. It's perfectly normal that it might remain for a few minutes after closing your browser.

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Doesn't "The reason i found this website is because..." sounds like he had never heard about this website before? – WarrenFaith Feb 5 '11 at 16:56
@oKtosiTe: Except that the output of netstat could be truncated. "" isn't a valid domain name. – Cody Gray Feb 5 '11 at 17:16
@Cody: It is, actually. .co is the top level domain for Colombia. – oKtosiTe Feb 5 '11 at 17:20
@oKtosiTe: Oh, maybe it is. It looks like they're selling .co domains globally now. Who knew. Either way, it's unlikely the netstat output indicates anything other than It looks like is just a squatter hoping Stack Overflow Internet Services will buy it from him. – Cody Gray Feb 5 '11 at 17:24
Indeed it does. @CodyGray – oKtosiTe Feb 5 '11 at 17:27

How about link pre-fetching as an explanation?

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Good thinking! (Though I'm not sure if that only applies to getting DNS records, or also really fetches content. The first won't show in the output of netstat, I think. The latter would indeed.) – Arjan Feb 5 '11 at 18:26

The output of netstat shows you reversed DNS addresses: a name based on an IP address. However, multiple names might exist for the same IP address.

Like both, and refer to the same IP address: But:

dig -x

...shows that this primarily maps to, even though


...shows the very same IP address.

So you probably visited one of the Stack Exchange sites?

Running netstat -n will show you IP addresses rather than (assumed) host names.

It might even be on the same server but that is not relevant here.

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