More than half of Europeans practise unsafe networking when they work away from the office, according to research by German remote access experts NCP Engineering.
A survey of 300 information-based workers across the UK, France and Germany found that 52% admitted they would access a network insecurely while working remotely.
Researchers said 82% of UK respondents knew the risks they were running and 90% said it was important to work securely. Even so, those who ran the risk said they worked either with company (47%) or personal data (53%).
NCP director Simon Ford said the findings were "very disheartening".
"This is extremely worrying," Ford said. "How data is stored and accessed has become a major security concern, with cases where vital company data has been lost or leaked due to employees accessing data via an insecure network."
Mobile data security is expected to be a hot topic at Mobile World Congress, which opens in Barcelona next week.
Most workers now use virtual private networks to access corporate data. But there is growing recognition of the need to build in more secure, hardware-based security routines that improve authentication and data protection.
It is expected that GMSA, the mobile industry's trade association, will use the show to make several announcements regarding SIM-based security.