"Rule 113. Treatment of the Dead, International armed conflicts

The prohibition of mutilating dead bodies in international armed conflicts is covered by the war crime of “committing outrages upon personal dignity” under the Statute of the International Criminal Court, which according to the Elements of Crimes also applies to dead persons"

( https://ihl-databases.icrc.org/customary-ihl/eng/docs/v1_rul_rule113 )