Has Kraken ever been hacked?

Excuse me, I am quite interested in the security of cryptocurrency exchanges. I understand that Kraken is a well-known and respected player in this industry. However, given the frequency of hacks and security breaches in the crypto world, I am curious to know if Kraken has ever been the victim of such an incident. If so, how did they handle it? Did they make any significant changes to their security protocols following the incident? Thank you for your time and attention.