Half of all medium to large organisations in the UK are failing to cope with the growing problem of image-based spam, new figures show.

While 97 per cent of respondents have anti-spam solutions in place, 50 per cent are not managing to deal with image-based junk messages, according to the latest research by email security firm PineApp.

The survey also found that 48 per cent of those businesses surveyed said the burden on bandwidth caused by image spam is a resource problem and 42 per cent admitted the exposure to malware was a concern.

“Embedding or attaching images such as .gif or .bmp files containing unwanted content into email is not new but it has grown fast and it is not being dealt with effectively," said Steve Cornish, UK sales and marketing director at PineApp.

"Spammers are always looking for new ways to bi-pass anti-spam solutions, such as attaching PDF files, and the industry is struggling to keep up."

Research carried out by Marshal earlier this year found that image spam was at an all time high, now accounting for more than half of all spam. Researchers at the internet security firm said the rise in picture-based messages was related to the decline in emails containing embedded URL links.