Sage's share price took a hit after it confirmed it had suffered a data breach impacting about 280 customers.
The accounting and business software vendor's share price dipped three per cent this morning after it admitted an internal login had been used to gain unauthorised access to customer information.
Asked what Sage partners should be advising concerned customers, a Sage representative said there is no specific guidance other than to direct them to its website, where it has published the number for a dedicated helpline.
"We cannot comment further whilst we work with the authorities to investigate - our customers remain our first priority and we are speaking directly with those affected," the representative said.
The Newcastle-based vendor, which is set to be the last homegrown listed UK tech giant standing following the proposed sale of ARM, said it is working closely with the authorities to investigate the situation.
Justin Harvey, chief security officer at Fidelis Cybersecurity, said: "UK companies using Sage will likely feel extremely unsettled by the news that the software company has been breached.
"If the reports are true and an internal login has been used, this means that the employee was either involved, fell victim to a phishing attack, or alternatively, the hacker had managed to gain a foothold in Sage's network and access the employee's login details."
He added: "Ultimately, as a FTSE 100 company, Sage's share price has already fallen and its reputation is likely to take a similar turn."
Sage's share price dipped from £7.39 to £7.15 this morning but has since rallied to £7.40.
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