Network security vendor Network Box has launched a Secure Blogging Guide giving corporate bloggers best practice advice on how to avoid being hacked.

The main threats to blogs are spam left in the comments section, which could contain malicious URLs, and SQL injection attacks that could exploit vulnerabilities in Blogger and Wordpress software, according to Network Box internet security analyst Simon Heron.

"As email becomes more difficult to get exploits through, the hackers are looking for other techniques," he said.

"If you see a link in a blog you're more likely to click on it than in the email environment because there is a greater sense of trust between the blogger [and the reader]."

The guide advises bloggers to restrict user access rights, keep blogging software up to date and check blogs regularly at weekends when attacks are most likely to occur.

Network Box also urges the use of Captcha or other authentication methods in order to reduce the likelihood of spam.

Corporate blogs are increasingly used to deliver marketing messages to customers, and Heron warned that firms must secure their blogs as they would a web site in order to avoid the brand damage that could ensue from a hacking incident.

"It will negate the benefits of a blog if you push out subliminal advertising and also give your customer a virus," he added. "None of the tips in this guide is rocket science and most only have to be done once."