Problem with some safari malware or trojan

Somehow, I seem to have got an annoying malware ad thing which is only affecting a couple of sites in safari. Mainly bbc.co.uk

It seems to be in my spare testing account as well so it looks like it's outside my home folder. It is very strange and subtle, it seem to be able to modify safari adblock extension. What it does is it will show an ad when Safari is opened and adblock will not block it even though the adress is in adblock, but if the page is reloaded it then will block it.

After a while it appears to disable Adblock. Uninstalling and reinstalling fixed adblock for a short time. There is no problem with Firefox.

This is the address of one of the ads on the bbc

Code:

http://adclick.g.doubleclick.net/aclk%253Fsa%253DL%2526ai%253DBpPreRuFwUor1O8OclQX97IGQDvr1o-oDAAAAEAEgADgAWKrq8Z9yYKWglYCYAYIBF2NhLXB1Yi0yOTE3MjkzODI4NTc4MzAzsgELd3d3LmJiYy5jb226AQlnZnBfaW1hZ2XIAQnaARNodHRwOi8vd3d3LmJiYy5jb20vwAIC4AIA6gIqNDgxNy9iYmNjb20ubGl2ZS5zaXRlLnd3dy9iYmNfaG9tZXBhZ2VfaW50-AKB0h6QA6gKmAPQBagDAdAEkE7gBAGgBh8%2526num%253D0%2526sig%253DAOD64_3bB3QUoTX5PGezmuGzTwgjiQJcUQ%2526client%253Dca-pub-2917293828578303%2526adurl%253Dhttp://ad.au.doubleclick.net/clk%3B276431482%3B103612918%3Bd

And this is what the ad looks like.



I have cleared out the safari caches directly from the cache folder. I'm at a bit of a loss as to how to track this down. I have run clam xv but nothing showed up. And reset Safari.

thanks.

 

It does not show up on Firefox. Also Safari Adblock extension keeps breaking, and I have to reinstall. The option for accessing the options or blocking an ad disappears. Also even though the address of the ad is blocked in Adblock, it won't block it the first time safari is opened.

The ad on the bbc is also the type of ad that they do not run. ie, it does not show up in Firefox even without any ad blockers running.

But mainly it's the way it keeps breaking Adblock.

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I've just checked Firefox again and I must have made an error before because the ad does show up there if I disable adblock. However with adblock enabled, it works fine in Firefox, ie it is permanently blocked.

But Safari adblock does not block it the first time it is opened, so would this indicate that there is simply a problem with Safari adblock?