Legacy IT infrastructure and business models pose the greatest threat to the global insurance sector, a poll of more then 900 senior industry experts has found.
The respondents argued that outdated technology is poorly equipped to handle the changing demands of the industry, and said there is an "urgent need" for modernisation.
Cyber crime was ranked the second greatest threat, with the insurance industry a particularly enticing target due to the volume of valuable data handled by the sector.
Inadequate responses to change management complete the top three risks, with new technologies radically changing insurance markets and customer expectations.
"The successful management of change is dependent upon how it's perceived," said Andy Moore, partner at PricewaterhouseCoopers (PwC) UK, which helped with the survey.
"Do these risks present an opportunity for insurers to proactively overhaul legacy systems, or cause a disruption that requires a reaction to remain relevant?"
Regulation was the fourth greatest threat identified, with the incoming standard IFRS 17 and consumer protection increasing compliance risk and implementation costs.
Climate change, reputational damage, interest rates, guaranteed products and social changes were also among the top 20 threats cited by the respondents.
Brexit was ranked 21 on the list of risks, with respondents outside the UK and EU saying they were insulated from any potential fallout, labelling Brexit "a non-event".
The survey was carried out by the Centre for the Study of Financial Innovation, which said that the tone of the responses were the most negative it had heard amid heavier regulation.
"The pressure applied by upcoming new accounting standards, particularly IFRS17, has amplified the issues," PwC's global insurance leader, Stephen O'Hearn said.
"The task of addressing and implementing these new regulatory standards, in the mandated timeframe, is proving to be a challenge for insurers everywhere."