Is Hedera secure?

I've been hearing a lot about Hedera Hashgraph recently, and I'm really interested in understanding its security features. Could you please elaborate on Hedera's security measures? I'm particularly concerned about the potential vulnerabilities it may face and how it addresses them. Also, how does Hedera compare to other popular cryptocurrencies in terms of security? I'd appreciate it if you could provide a detailed overview of Hedera's security framework and assurances.