Over 25% of UK councils have had their computer systems breached over the past five years, activists say.
A report on the privacy group Big Brother Watch, based on freedom of information requests found 114 tips experienced at least one incident between 2013 and 2017.
The group said it was “shocked” that the staff often lacked the cyber-training.
The Local Government Association, said councils took their privacy responsibilities “very seriously”.”Protect the citizens’
Big Brother Watch has said it has received responses from 395 local authorities, and that, of the 114 who said their systems had been breached, 25 reported having suffered a data loss or breach as a result.
He said that most of the success of cyber-attacks that began with the so-called phishing scams, designed to trick the personnel to disclose a password and other data.
Big Brother Watch said the humans were the weak link in the cyber-security chain, and the risk could be reduced by introducing training for all employees of the council.
Three-quarters of councils do not provide mandatory it security training, and 16% did not provide any at all, according to the report.
Jennifer Krueckeberg, researcher at Big Brother Watch, said: “it could be assumed that they [councils] doing their best to protect their citizens’ sensitive information.
“Local authorities need to take urgent action and make sure that they meet their responsibility to protect the citizens,” he added.
Based on the FoI data, the report estimated that the number of cyber-attacks against local authorities, which contain the data of millions of residents, to 98 million euros between 2013 and 2017.
This amounts to 37 attacks every minute.
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A Local Government Association spokesman said: “Very few of these attacks manages to breach the firewall, or scanning systems”.
He added that the councils are working with the National Cyber Security Centre to ensure that their systems are as rugged and durable as possible”.
It comes as figures released at the beginning of this month, the National Cyber Security Centre, has shown in great Britain is to fend off millions of attacks a month.
They have shown that the tips are among the organisms most commonly imitated, e-mail, designed to gain confidence.