(Accidentally?) hired into the wrong position

A company was hiring several developers. Among them a embedded software developer position with some very strict requirements (like 10+ years of experience with C) that I in no way qualify for (I'm a web developer, but embedded programming has been a hobby of mine for years)

I applied for a web developer position at the company, and was called in for an interview.

At the interview the guy interviewing me starts talking about embedded programming, and I start wondering if maybe I put it on my application as a "hobby" and that's why he mentions it.

So we discussed embedded programming for almost an hour - then he tells me they'll get back to me.

Very confused I went home and checked my application - but there is no mention of embedded programming.

2 days later I receive an offer for a embedded developer position with a salary way above the range mentioned for the web-developer position.

Though it's quite likely that they mixed my application up with someone elses, could accepting the offer (for a position I didn't apply for) land me in any trouble?

Entering into a working relationship is an act of mutual trust. An interview builds upon information in a CV, but it does not replace it. If you are about to enter into a working relationship based on a mixed up CV, you have one option:

Come clean. All cards on table.

And if you are at all in doubt about this, you've failed to view the situation from their side. Had it been your company, would you prefer for a candidate to correct a mistake like this before you trust him your money and your project? Or would you be fine with him knowingly entering into a working relationship based on a mistake?

I suspect you field this question because you are looking for someone to deter you from this obvious truth. Don't fall into that trap. You know what's right.

The outcome of this? I expect a bunch of goodwill, a good stomach feeling and most likely the chance to keep the embedded position or at least a good shot at growing into it from the web development position that you surely will be offered.

The outcome of not doing it? The birth of a very nasty imposter syndrome. 6 months down the line, when low level allocation bugs have crept in and people begin to take notice of instability, do you want to be the guy that fails a code review, exposing the ugly truth you knew all along? Do you want to skate around your web development background going forward? Fake experience you don't have? Believe me, things only get worse from here.

Do the right thing. Stop thinking twice.