Can any PSP be hacked?

Could you elaborate on the vulnerability of Payment Service Providers (PSPs) to potential hacking attempts? Is there a specific type of PSP that's more prone to breaches? What kind of security measures do these institutions typically employ to safeguard their systems and user data? Furthermore, are there any recent examples of successful hacking incidents involving PSPs, and what can we learn from them to prevent similar occurrences in the future?