Most lenses will have chromatic aberration in an extremely strong contrast situation like those branches against the sky. I wouldn't worry too much about that, except....

1. If you have a filter on the lens, try without it... some filters amplify CA.
2. You might try stopping down a bit to see if that reduces CA. The image EXIF shows this shot was done wide open, f/3.5 at 18mm. CA tends to be worse in out of focus areas. Stopping down to a middle aperture like f/5.6 or f/8 will increase depth of field and with more in sharp focus, it should make for less CA.
3. You might be able to "tune out" the CA in post-processing. Depends upon what software you use. "Lens profiles", if software supports them, can do it automatically.... at least to some extent. (Canon's own Digital Photo Pro RAW conversion software should have built in profiles for most Canon lenses.... Adobe Lightroom has many of them, too.)

If not already using one, get the appropriate lens hood (different versions of EF-S 18-55mm use different hoods, so be VERY careful to select the correct one). A hood may help with better overall image contrast and avoid some flare, though it likely won't do much to reduce CA. A hood also helps physically protect the lens while it's in use (better than the thin piece of glass in a "protection" filter ever could).

Lens is a Canon EF-S 18-55mm... a kit lens that's often included with APS-C camera models. There have been six or eight different versions of that lens over the years. This is probably one of the more "basic" models since it lacks IS and doesn't appear to have STM focusing motor. "Early" models of that lens don't have as good image quality as later. Early ones also commonly have a front barrel that rotates during focusing, which can be a pain in the arse when using a circular polarizing filter.

The camera used is an 18MP Canon 550D/T2i.

Frankly, it's pretty amazing just how good images are possible even with inexpensive "kit" lenses these days.

The IS (image stabilized) lens will be helpful for shots like this where you are hand holding 1/30 seconds. It it's also the STM version, that's likely one of the newer ones and will be faster, quieter focusing, too.