  MICROSCOPE's space test of the weak equivalence principle (WEP) is based on
the minute measurement of the difference of accelerations experienced by two
test masses as they orbit the Earth. A detection of a violation of the WEP
would appear at a well-known frequency $f_{\rm EP}$ depending on the
satellite's orbital and spinning frequencies. Consequently, the experiment was
optimised to miminise systematic errors at $f_{\rm EP}$. Glitches are
short-lived events visible in the test masses' measured acceleration, most
likely originating in cracks of the satellite's coating. In this paper, we
characterise their shape and time distribution. Although intrinsically random,
their time of arrival distribution is modulated by the orbital and spinning
periods. They have an impact on the WEP test that must be quantified. However,
the data available prevents us from unequivocally tackling this task. We show
that glitches affect the test of the WEP, up to an a priori unknown level.
Discarding the perturbed data is thus the best way to reduce their effect.
