  Meson decays offer a good opportunity to probe new physics. The rare kaon
decay $K^+ \rightarrow \pi^+ \nu\bar{\nu}$ is one of the cleanest of them and,
for this reason, is rather sensitive to new physics, in particular, vector
mediators. NA62 collaboration, running a fixed-target experiment at CERN,
recently reported an unprecedented sensitivity to this decay, namely a
branching fraction of $BR(K^+ \rightarrow \pi^+ \nu\bar{\nu}) =
(11^{+4.0}_{-3.5})\times 10^{-11}$ at 68\% C.L. Vector mediators that couple to
neutrinos may yield a sizeable contribution to this decay. Motivated by the new
measurement, we interpret this result in the context of a concrete $Z^\prime$
model, and put our findings into perspective with the correlated $K_L
\rightarrow \pi^0 \nu \bar{\nu}$ decay measured by KOTO collaboration, current,
and future colliders, namely the High-Luminosity and High-Energy LHC.
