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Actually - this is not securre enough.

The problem is that you can pass many, many bad things via JDBC url - when the values are not properly escaped. It's enough to pass ; as value of any of the paremeters you pass from extra. And when it happens, the user who has permission to configure the connection via UI might even perform RCE in a number of cases.

The recommendation here is:

• only allow fixed values to be passed via extra (bool for example) to control how the JDBC URL is constructed
• only allow "free-form" parameters to be passed by init parameters of the operator/hook - that can only be done by the DAG author, and DAG author by definitiion and security model of Airflow https://airflow.apache.org/docs/apache-airflow/stable/security/security_model.html can do more than connection editing user
• sanitize the input (but this one is potentially very difficult)

While we already warn against the potentially Conection editing user being able to have more capabilities - so this is not strictly security issue, this is part of "security hardeninig" - we should not add "easy" ways for those users to be able to perform all kinds of attacks.

I guess this also applies to the already existing Principal and Proxy User fields? I see that they only validate if a ; character was passed

I guess this also applies to the already existing Principal and Proxy User fields? I see that they only validate if a ; character was passed

I think there are more validations needed. Passing arbitrary parameter as path to jdbc is dangerous (what happens if for example jdbc driver displays content of the file when it is wrong and you pass "/etc/passwd"` ?. This is just example, it could be even more diastrous - printing more secret keys and secret variables stored somewhere on remote system. I am not sure if you can make it "secure" when this parameter is passed via UI and free-form.

There are only few values allowed for transportMode I guess, so it is safer to enumerate them rather than pass directly. When it comes to password, there is a question how ; is going to be passed (i..e what form of escaping should be there)?

I guess this also applies to the already existing Principal and Proxy User fields? I see that they only validate if a ; character was passed

I think there are more validations needed. Passing arbitrary parameter as path to jdbc is dangerous (what happens if for example jdbc driver displays content of the file when it is wrong and you pass "/etc/passwd"` ?. This is just example, it could be even more diastrous - printing more secret keys and secret variables stored somewhere on remote system. I am not sure if you can make it "secure" when this parameter is passed via UI and free-form.

There are only few values allowed for transportMode I guess, so it is safer to enumerate them rather than pass directly. When it comes to password, there is a question how ; is going to be passed (i..e what form of escaping should be there)?

Thanks for the insight. I will see what I can do.