According to a report from security firm Imperva, about 80% of the comment spam traffic is generated by 28% of attack sources while 58% of the all attack sources are active for long periods of time.
The report suggests, since a small number of attack sources are responsible for the majority of comment spam traffic, it is advisable to identify the comment spammers early to block their attacks on their way.
Imperva CTO Amicahi Shulman said that latest Hacker Intelligence Initiative Report reveals that a relatively small number of attack sources create the majority of comment spam, oftentimes leveraging automated tools to reach a maximum number of targets.
"Comment spam attacks can cripple a website, impacting uptime and compromising the user experience," Shulman said.
"Quickly identifying the source of an attack and blocking comments from the source can greatly limit the attack’s effectiveness and minimize its impact on your website."
Spams are unsolicited web messages sent over to large numbers of users, for advertising, phishing, spreading malware which helps spammers gain profit.
With the development of web technologies, spammers are now emerging from traditional way sending spams through mail, and now planting spam comments into forums, comment fields, guest books, and even websites like Wikipedia, which allow user generated content to be published.
Comment spammers are lured by search engine optimisation techniques to use a promoted site for advertisement and malware distribution.
The report has been prepared by monitoring of comment spammers’ activity on more than 60 web applications during two weeks, between 1 September to 14 September in 2013.
The study also examined the stages a spammer follows to generate comment spam and the various ways that comment spam can be automated to allow attackers to scale their efforts.
