Hi all!

Im guessing that 90% of you people who post here at Astahost have your own webpages, blogs, forums and such stuff. I myself have myown too. The purpose of this post is not to talk about my web neither it's a way to get you to click link to my page. It's just about this issue I have with spammers. They constantly come back to my guestook, and enter bullsh*t to forms, like links to drugstores, viagra, porn, and such stuff. As every webmaster I must stay in track with them, and every day I constantly delete junk posts on guestbook...
Now my question is how to workaround this issue? Im aware of banning specific, or whole range of IP's from accesing my domain, but what to do If spammers keep comming back, from different IP adresses? Probably they are not stupid so they use public proxy servers, probably annonymouse one. So, what I can do about it? If anyone have idea, or some php script that may scan posts for specific words, and ignore them if its some bad stupid stuff. My guestbook don't have such stuff imlemented... And finally here is how it looks when spammers attack your guestbook:
A link to image

What guestbook are you using ? Third party code or one written on your own ? If you wrote it, you can easily introduce some GD tricks, and make the addition process be accompanied by one of the CAPTCHA (Completely Automated Public Turing Test to Tell Computers and Humans Apart) diagrams .. the images generated by GD containing numbers/letters which one has to enter to verify human presence...

Most of these stuff are added by spam bots - no one has the time to go around on millions of pages and add these manually. If you can implement the CAPTCHA Verification that'll get rid of it for once and all.

Oh, yes, Im aware of that... I could say Im using my own code for guestbook... so anyway, is there some tutorials for implementing CAPTCHA, or I just go to google and search a bit?

There is one trick you could use that would place a cookie on the offenders computer, then unless they use many different machine to attck you (Not too likely, but possible) you can deny them even posting, at least until they figure out you have put a cookie, but when the cookie is put on them everytime then soon they will get tired of attacking you and then going and deleting the cookies, which is almost as bad as spam to them.

This way even if they have a dynamic IP then then cookie is still on the machine.

hmm, not bad idea too, maybe I'll try that, and see what's the best solution. thanks Houdini!

Well I had similar problems, but after I put an image with random numbers and letters, they stopped doing it, so it helps.. by the way I don't think cookies would help, unless it is some stupid guy attacking your guest book..

here is a quite good code to generate random numbers and letters, but i prefer numbers in the image, using gd you can make your own images as you like.



so echo random_chars(); will make an 6 chars random value, you can set any value you want.

The same thing started happening on my friend's blog: all of a sudden, he was getting a bunch of spam comments, sometimes five at a time or more. Not long after that started, Blogger introduced image verification for blog comments. He turned it on, and the spam comments came to a complete deadstop. Either the spammers were all bots, or they were people who were blind.

Hi,
after lot's of trouble, I sucessfuly implemented CAPTCHA into my guestbook. You can test how it works here
Try it, and post here if you find errors/bugs/etc. thanks all!

Good man great I just saw it. Good one Well done.

One simple way is to add verification to your guestbook which is an image that has random letters and/or numbers that must be entered before you submit your comment on the guestbook.

If you cannot do that, then perhaps you can block IP addresses. Once you get enough spam on your guestbook, you should be able to see repeating IP addresses. So you should be able to block them if your guestbook supports that.

In my own case, I ended up doing both. Adding word verification and blocking IP addresses and I haven't had a problem with spam in the longest time...knock on wood.