Is this a False Positive

[visage]

My MB History has flagged C:/Windows/System32/drivers/nvlddmkm.sys as an Unknown Rootkit Driver, can anybody tell me as to whether this is actually a False Positive or not.

[thisisu]

Hello visage,

We need more information about this potential false positive. Please read: 

 

[miekiemoes]

Hi,

If the scanner sees a legitimate file as "Unknown.Rootkit.Driver", then this means there's probably indeed a rootkit present (as we have seen with certain old 0access variants) where the files are "forged" by the rootkit. Meaning, reads through WinAPI differs from the contents readen through low-level disk access. In such cases, malwarebytes fixes this and restores this with a "clean" one.
It doesn't always mean that you were indeed dealing with a rootkit. We've seen some other cases as well causing files to be forged (by some legitimate software - eg: Rollback Rx PC or Zemana)