Vet giant CVS Group said it has suffered “considerable operational disruption” after a cyber incident over the past week.
The company, which runs around 500 veterinary practices globally, said it reacted to limit the impact of the attack but witnessed particular disruption to its UK operations.
The incident involved “unauthorised external access” to a limited number of its IT systems, CVS said.
In response, the company took its IT systems temporarily offline in order to stop wider unauthorised access.
It said this was successful in stopping the hackers gaining further access to its systems but had a “considerable” impact on operations.
Specialist third party consultants are investigating the incident and the group has also informed authorities such as the Information Commissioner’s Office “due to the risk of malicious access to personal information”.
The firm, which employs over 9,000 staff, said its UK operations have been particularly affected by the attack and its response.
“Through the efforts of our colleagues, we have continued to provide our usual high levels of clinical care to clients and patients at the majority of our practices,” CVS said.
“IT services to our practices and business functions have now been securely restored across the majority of the estate; however, due to the increased levels of security and monitoring, some systems are not working as efficiently as previously and this is likely to result in an ongoing operational impact.”
The London-listed company said it is accelerating plans to move its practice management system and relevant IT infrastructure to the Cloud as a result.
It said this and the security response to the attack “are likely to have an impact on operations for a number of weeks”.