Contact Form Spam
Contact forms are a fantastic way to allow visitors to your website get in touch directly from your site. People can fill the form in with their query which your website then takes, generates and email and send through to you. Contact forms are not however immune to spam and often you may find you get sent nonsense forms which have actually been filled out by automated bits of software called bots.
These bits of software crawl the World Wide Web looking for forms to fill in and send. Their aim is to find similar forms which are used to submit website content such as comments on blog articles or website guest books. They fill out as much of the form as they possibly can including links in the main body of the text. These links are valuable because they can assist will search engine optimisation and increase the traffic a website receives from search engines like Google.
More sophisticated spammers will not include a link and just use text they can then use to identify the website and form that has been submitted. They can then build a list of websites that are the most vulnerable to automated link spam.
While this may be annoying they do not pose a serious problem for most contact forms and can just be ignored. It's important to not add them to your spam filter as this could lead to missing genuine contact requests. Should the amount of spam become unmanageable there are methods you can use to reduce spam contact forms such as captchas or hidden fields which will be seen by bots but not human visitors.