Image spam

[Charles Lacroix]

On Wednesday 28 February 2007 14:58, Chris Yuzik wrote:
> Renee Gehlbach wrote:
> > I see plenty of ham w/ attached gifs through one of my servers, but
> > very little from others.  Yet another example there being no one
> > standard pattern for ham.
> >
> > Hmm....  why exactly would this be preferable?  We tend to set email
> > clients not to permit the display non-attached images in html
> > messages.  Thunderbird and Squirrelmail, I believe, even do this by
> > default.  I've heard plenty of arguments against allowing email
> > clients to go retrieve pictures, do you have arguments for it?
> >
> > Do you use Fuzzy OCR?  It's the only way I've found to really target
> > image spam.
>
> Renee,
>
> We are experimenting with Fuzzy OCR, and while in our tests it does
> catch some image spam, it's not doing very well with image spam where
> the image has background noise, slanted text, etc.
>
> I agree that having a link to an external image is not (necessarily) a
> good idea, and in fact can activate web-bugs and such on spam that does
> manage to get through.
>
> I find it interesting that Barracuda is advertising that they block "all
> image spam". Abaca is advertising they block 99% of all image spam. How
> are these guys achieving this success rate?
>
> Chris


Hi,

I catch tones of image spam with Fuzzy OCR, which is ran just after Barracuda 
anti-spam firewall 400 is done with it's filtering.

bottom line, we can't say "all" image spam 

On the other hand, the Fuzzy OCR has problem with some 
french image signatures where it detects about 15 keywords 
which aren't even into the image. I lowered the score so it doesn't hit so 
hard, and i also whitelisted the few individuals which this caused me 
problems.

Charles