In 2023, the security problems on Bitcoin were mainly attacks on wallets and exchanges.
What happened with wallets and exchanges have nothing to do with Bitcoin security. Because a wallet can be good or bad, open source or close source, custodial or self custodial, an exchange can be centralized or decentralized, but all of them has nothing to do with Bitcoin protocol. If they have security weakness and holes for hackers to compromise their wallets or exchanges, it's their issue, not Bitcoin protocol.
Hackers did crazy things with phishing, malware, and schemes to get people's private keys. In addition, there were some bugs in the code that let vulnerabilities slip through, but don't worry, that was quickly fixed with updates.
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