Okta Verify TOTP secret key can be extracted easily using curl and the code below.

Get the content of the QR for Okta Verify app setup. It looks like this: oktaverify://[email protected]/?t=XXXXX&f=YYYYY&s=https://DOMAIN.okta.com&issuer=DOMAIN.okta.com&isIdxEnabled=true
Replace XXXXX, YYYYY and DOMAIN to your values in curl below:

curl --request POST \
  --url https://DOMAIN.okta.com/idp/authenticators \
  --header 'Accept: application/json; charset=UTF-8' \
  --header 'Accept-Encoding: gzip, deflate' \
  --header 'Authorization: OTDT XXXXX' \
  --header 'Content-Type: application/json; charset=UTF-8' \
  --header 'User-Agent: D2DD7D3915.com.okta.android.auth/7.17.1 DeviceSDK/0.19.0 Android/13.1 unknown/Xiaomi' \
  --data '{
	"authenticatorId": "YYYYY",
	"device": {
		"clientInstanceBundleId": "com.okta.android.auth",
		"clientInstanceDeviceSdkVersion": "DeviceSDK 0.19.0",
		"clientInstanceVersion": "7.17.1",
		"clientInstanceKey": {
			"alg": "RS256",
			"e": "AQAB\n",
			"okta:isFipsCompliant": true,
			"okta:kpr": "SOFTWARE",
			"kty": "RSA",
			"use": "sig",
			"kid": "-e37YhNPIhjym6cHQBey0XlJfrcxKg31XjQ6hPRKQao",
			"n": "vnvko4eUTu7FwUftRYI1ergvaWJ0NDbL8W2fvUWswBP7vYZOC21R4n18k7INLCfxHvfW0pQOY_jO3H1d_QXJJt1yRZUYkiQHV6yc1o14x_cfuS_5q6ZpKk_MbTik-kX1oebXlcj7MWP1I7E3TDsUAnsvwp0oP5K7eDN_QJYfaP0nrxQQaDFDKzJNv_jSucCSxO_aQoNNX-vyrUTxqvC9qfQ7rnC7hg5iXbJ-HWrX1494jGIfuDAm32-W5HlgZb0Q69IQevLbuI55BsCRPZwF-ef4zQgHV6N8KmDdpiOhXfAXoilf8w8dH1ccUIXX_sA9WQMVCc-llngS7LractTvQQ"
		},
		"deviceAttestation": {},
		"displayName": "Bitwarden",
		"fullDiskEncryption": false,
		"isHardwareProtectionEnabled": false,
		"manufacturer": "unknown",
		"model": "Xiaomi",
		"osVersion": "25",
		"platform": "ANDROID",
		"rootPrivileges": true,
		"screenLock": false,
		"secureHardwarePresent": false
	},
	"key": "okta_verify",
	"methods": [
		{
			"isFipsCompliant": true,
			"supportUserVerification": false,
			"type": "totp"
		}
	]
}'

Send this request and get sharedSecret value from the response. This is your TOTP secret key. Paste it to the corresponding app (e.g. Bitwarden) and enjoy!

Example curl request:

curl --request POST \
  --url https://state.okta.com/idp/authenticators \
  --header 'Accept: application/json; charset=UTF-8' \
  --header 'Accept-Encoding: gzip, deflate' \
  --header 'Authorization: OTDT ftC9ysuejN2CYOHgbv19M9ysuwjsjySYAn4D' \
  --header 'Content-Type: application/json; charset=UTF-8' \
  --header 'User-Agent: D2DD7D3915.com.okta.android.auth/7.17.1 DeviceSDK/0.19.0 Android/13.1 unknown/Xiaomi' \
  --data '{
	"authenticatorId": "butlme8hf90eAYmyK537",
	"device": {
		"clientInstanceBundleId": "com.okta.android.auth",
		"clientInstanceDeviceSdkVersion": "DeviceSDK 0.19.0",
		"clientInstanceVersion": "7.17.1",
		"clientInstanceKey": {
			"alg": "RS256",
			"e": "AQAB\n",
			"okta:isFipsCompliant": true,
			"okta:kpr": "SOFTWARE",
			"kty": "RSA",
			"use": "sig",
			"kid": "-e37YhNPIhjym6cHQBey0XlJfrcxKg31XjQ6hPRKQao",
			"n": "vnvko4eUTu7FwUftRYI1ergvaWJ0NDbL8W2fvUWswBP7vYZOC21R4n18k7INLCfxHvfW0pQOY_jO3H1d_QXJJt1yRZUYkiQHV6yc1o14x_cfuS_5q6ZpKk_MbTik-kX1oebXlcj7MWP1I7E3TDsUAnsvwp0oP5K7eDN_QJYfaP0nrxQQaDFDKzJNv_jSucCSxO_aQoNNX-vyrUTxqvC9qfQ7rnC7hg5iXbJ-HWrX1494jGIfuDAm32-W5HlgZb0Q69IQevLbuI55BsCRPZwF-ef4zQgHV6N8KmDdpiOhXfAXoilf8w8dH1ccUIXX_sA9WQMVCc-llngS7LractTvQQ"
		},
		"deviceAttestation": {},
		"displayName": "Bitwarden",
		"fullDiskEncryption": false,
		"isHardwareProtectionEnabled": false,
		"manufacturer": "unknown",
		"model": "Xiaomi",
		"osVersion": "25",
		"platform": "ANDROID",
		"rootPrivileges": true,
		"screenLock": false,
		"secureHardwarePresent": false
	},
	"key": "okta_verify",
	"methods": [
		{
			"isFipsCompliant": true,
			"supportUserVerification": false,
			"type": "totp"
		}
	]
}'

Example server response:

{"id":"pfdkd1fhmysksidj8eS297","authenticatorId":"ospwid8oaoaieiAYmyJ297","key":"okta_verify","status":"ACTIVE","type":"app","device":{"id":"guokdhorufsGaL1vVE297","status":"CREATED","created":"2023-07-30T16:56:19.000Z","lastUpdated":"2023-07-30T16:56:19.000Z","profile":{"displayName":"Bitwarden","platform":"ANDROID","manufacturer":"unknown","model":"Xiaomi","osVersion":"25","registered":true,"managed":false,"secureHardwarePresent":false},"_links":{"activate":{"href":"https://state.okta.com/api/v1/devices/gupaowiiehfsGaLkdido297/lifecycle/activate","hints":{"allow":["POST"]}},"self":{"href":"https://state.okta.com/api/v1/devices/guokmyauajwnslspwa7","hints":{"allow":["GET","PATCH","PUT"]}},"users":{"href":"https://state.okta.com/api/v1/devices/gupahuwoeprpodsjos7/users","hints":{"allow":["GET"]}}},"clientInstanceId":"cliososiejrbsjuiw7"},"user":{"id":"00kslsppwwjrjrurhnej297","username":"[email protected]"},"methods":[{"id":"oudjeoekeF2MOZGc297","type":"totp","createdDate":"2023-07-30T16:56:19.000Z","lastUpdated":"2023-07-30T16:56:19.000Z","sharedSecret":"YOUR_TOTP_SECRET_KEY_HERE"}],"createdDate":"2023-07-30T16:56:19.000Z","lastUpdated":"2023-07-30T16:56:19.000Z","_links":{"self":{"href":"https://state.okta.com/idp/authenticators/pospajehebrbsnksl97","hints":{"allow":["GET","DELETE"]}}}}

All data in examples has been modified to garbage value.

Notes:

This request creates a new device named "Bitwarden" in https://DOMAIN.okta.com/enduser/settings in "Security Methods" block
If it returns invalid session error, probably your QR's content is expired
If it returns 400 and complains to clientInstanceKey, try to replace kid and n to values from https://DOMAIN.okta.com/oauth2/v1/keys

deron-dev/OktaVerify_TOTP_Key_Exteaction.md