Yes — this looks like chromatic aberration from the lens, not a lighting problem. Specifically, the blue/green fringing described is consistent with axial (longitudinal) chromatic aberration, sometimes called bokeh fringing. It’s common with fast lenses, especially when used wide open, and even expensive lenses can show it.

That doesn’t necessarily indicate a bad lens. High-end lenses can still have some longitudinal CA, while cheaper lenses more often show lateral (transverse) CA, which behaves differently and can appear at any aperture.

The amount shown here sounds minor and generally isn’t something to worry about. If it bothers you in real-world images, software such as Lightroom can often reduce or correct visible fringing.