SDE3 interviewer here: Is helping a known candidate before an interview cheating? I want to refuse to help, what to tell?

I’m an SDE3 at my company and I’ve recently started taking first-round interviews.

Today, I suddenly got a message from a colleague from another team asking if I’ll be coming to the office tomorrow. We’ve hardly spoken apart from a few Teams chats, so I found it a little unusual.

She then messaged me saying that she came to know that her acquaintance has an interview scheduled next week and that I’ll be taking the interview.
I haven’t opened the latest message yet.
I checked the candidate’s resume and noticed that she studied at the same college and in the same batch/year as my colleague, although they were in different batches. So they could potentially be friends or at least know each other well.

Now I’m wondering what the colleague might be trying to ask and whether it would be appropriate for me to help her acquaintance in any way.
Personally, I don’t think this is a good practice. If I give the candidate interview questions, hints, areas to prepare, or any kind of inside information, wouldn’t that be unfair to the other candidates who are going through the same process without knowing anyone on the interview panel?

It also feels like cheating the candidates who actually deserve the opportunity based on their own preparation and skills.

Our hiring process is also being monitored quite closely. The hiring manager and another manager review the interview feedback, and we’ve been specifically instructed to ask fairly deep DSA questions, cross-question candidates, and properly assess their problem-solving ability.

So I definitely don’t want to do anything that could compromise the integrity of the interview or put me in a difficult position professionally.

For people who have been interviewers or worked in hiring: **How would you handle this situation?**
Would you simply ignore the message, or politely tell the colleague that since I’m on the interview panel, I can’t share anything about the interview or help the candidate prepare specifically for it?

Also, would this be considered a conflict of interest if the interviewer knows the candidate personally or through a colleague?