Native Secure Enclave backed SSH keys on macOS

Post by [deleted] » Sun, Nov 23, 2025, 8:13 PM UTC

arianvanp wrote: post #54

gruez wrote: post #50

Earlier quoted context omitted.

>The key is stored encrypted with a unique symmetric key that only your secure enclave knows until the point that you export it. It then re-encrypts it with the password. But what's the security benefit of this compared to having a keyfile? So far as I can tell from the commands you provided, there's no real difference, aside from a hacker having to modify their stealer script slightly.

Why is it more secure: a key file on disk is decrypted into memory every time you enter your passphrase. It means the key is around in plain text in the memory of ssh or ssh-agent. Which means it's extractable by an attacker. An exportable key does all the signing inside the secure enclave and never exposes the decrypted key to OS memory. The exported key you can keep in a safe for disaster recovery. You shouldn't ke…

Post by aaomidi » Sun, Nov 23, 2025, 8:18 PM UTC

jedberg wrote: post #13

If I understand correctly, this means you can't back up the private key, correct? It's in the Secure Enclave, so if you lose your laptop, you also lose the key? Since it looks like export only really exports the public key not the private one? Probably not the worst thing, you most likely have another way to get into the remote machine, or an admin who can reset you, but still feels like a hole. Or am I missing somet…

Post by gruez » Sun, Nov 23, 2025, 8:23 PM UTC

arianvanp wrote: post #72

gruez wrote: post #67

Earlier quoted context omitted.

>It means the key is around in plain text in the memory of ssh or ssh-agent. Which means it's extractable by an attacker. An exportable key does all the signing inside the secure enclave and never exposes the decrypted key to OS memory. But malware can just tell the secure enclave to export the key? Yes, they'll have to write new code to do that, but it's not particularly hard (it's 1 line code from your example abov…

The export operation is guarded by TouchID. So the malware needs to trick you into performing the TouchID gesture. But yeh the malware only needs to trick you to hit TouchID once. Instead of on each sign operation. So if that's in your threat model don't make the key exportable.

Post by watermelon0 » Sun, Nov 23, 2025, 8:32 PM UTC

Post by vlovich123 » Sun, Nov 23, 2025, 8:33 PM UTC

pi-rat wrote: post #46

jedberg wrote: post #34

Earlier quoted context omitted.

I've been in the security space for 25 years, and understand the theory of PKI. But I've also been in the ops space for 30 years, and understand that if you don't balance security theory with operational practice, critical business functions can fail. Ideally yes, the private key is never seen. In reality, it needs to be backed up in a secure place so it can be restored in the event of a failure.

You can use more than one key you know. Keep the private key you actively use in the secure enclave. The system you actively use is most at risk. Keep a secondary offline private key as backup. You can generate and store it in a secure location, and never move it around. Airgapped even if you want. You could even use a yubikey or other hardware for the secondary key giving you two hard to export keys. Distribute pub…