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Some more details of context together with dimensions would be helpful, but ‘star-holes’ in rocks are a ‘thing’ and they’re found all over the place. Yours is very similar to this one, which stoked up a mystery when discovered in Volda in Norway in 2007.
The consensus is that these holes mostly relate to blasting (sometimes failed), quarrying, exploratory drilling and construction work from the late 1800s through to the early 1900s. An investigation by the local Norwegian newspaper (after consultation with some blacksmiths) established that they’re quite common in particular localities and it was suggested this one was likely made in the 1930s. Similar holes are found with 5, 6, 7 or more ‘points’ to the star and they’re said to relate to the use of drill heads with multiple sides.
There are numerous examples cited and pictured at “Relics of the Gods” website linked below, with an alternative explanation that they relate to ancient civilisations. Not a view that I support, but I still struggle to see how a drill bit can produce a star-shaped hole unless we’re talking about a hammer drill:
STAR HOLES
There’s some helpful discussion here about similar holes found at Flynt Quarry, Monson MA in the USA and the rifling effect that can produce the apparent points:
Stones of Northeastern U.S. - Quarry - Pentagonal & Star Holes
In one case, for a group of three holes found in Minnesota and claimed in a newspaper to have been made by Viking explorers (something else that isn’t a view I support), a local lady stepped forward and confirmed that her father had made them in 1908 during an abandoned attempt to blast some rocks for building stone.
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