What does it show?

Color profile or profiles that can be found in pdf.

How to interpret the result?
If there is a -Output Device profile- in the list, and it is followed by the -cmykData- remark, then the color space of the coupled color profile is appropriate. However, it does not mean necessarily that the type of color profile was selected properly.

ICC color profile embedded in PDF

What does the warning mean?
ICC color profile of pdf
PDF contains icc color profile.
The majority of printing companies does not use the color profile coupled to the pdf. If you have no detailed knowledge about color profiles, then it can be removed from the pdf, because it only increased the size of pdf.
How the problem could be resolved?
The converters mentioned below can remove Icc color profile from the pdf.
Deleting color profile from pdf.
Deleting color profile from pdf.