BAK files from Canvas are just backups of its own drawings and can be recovered using the program. Once recovered you may work with them much like with any other Canvas drawing. There is a slight possibility that you can just rename bak to cvs in this case and it will work, however this could not be verified.
Convert Canvas drawing backup file to Canvas bitmap or vector image.
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert bak to cvs on Windows
A drawing software used to create technical illustrations and graphics
Convert from bak file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.