British mobile device detection company 51Degrees used by the likes of Unilever, T-Mobile, IBM, and Microsoft, has been hacked.
The Reading-based company sells device detection allowing customers such as Hyundai, Deloitte, and Heineken to identify quickly a web site visitor's device.
Founder James Rosewell says in a letter to customers that the site was popped for 20 minutes on May 8th.
"It has come to our attention that the website was the victim of a cyber attack between 5:21am and 5:40am (GMT) on Sunday 8th May 2016.
"We do not believe any personal information including payment information, email addresses, and contact names has been compromised.
"To prevent a recurrence of the attack, we have closed the exploit used by the attacker."
Rosewell did not specify the type of exploit used, nor the areas the attacker access.
He says unspecified "additional security measures" have been implemented to harden the site.
It has contacted the UK Cyber Crime Action Fraud unit and handed over relevant information.
Little else is known about the attack and there appears to be no activity on social media or across the web regarding the hack. ®