SEO poisoning, also known as search poisoning, is an attack method in which cybercriminals create malicious websites and use search engine optimization tactics to make them show up prominently in search results. The sites are associated with terms that large numbers of people are likely to be using in searches at any given time, such as phrases related to holidays, news items and viral videos. According to Websense Security Labs, up to a quarter of the first page of search results for trending topics are linked to malicious websites.
The attackers create websites with names and descriptions associated with popular or trending topics. For example, in the weeks leading up to Halloween, the attackers might launch sites offering free templates for Halloween costumes; in the weeks or months leading up to Christmas, they might launch holiday recipe sites. The sites might be devoid of relevant content or might feature content stolen from valid sites. The real purpose, however, is to infect visitors with malware or fraudulently access sensitive information to be used for identity theft. Malware on the site may coopt the visitor's computer for a botnet or install a Trojan horse to steal login information. Another ploy is to present the user with a product that they think they are purchasing to access their credit card details.
To protect yourself from search poisoning attacks, security experts recommend that you keep your browser and antivirus software up to date, avoid clicking suspicious-looking links and never provide personal information online unless you're certain the site is valid and the transaction is secure.