In　programmable　networks,　some　networking　systems　coordinate　data　plane　switches　to　realize　in-network　functions　(e.g.,　in-band　network　telemetry).　However,　the　vulnerabilities　of　inter-device　coordination　are　still　largely　unknown　and　neglected,　which　is　highly　concerning　given　the　increasing　popularity　of　this　paradigm.　In　this　paper,　we　identify　three　attack　scenarios　built　upon　such　vulnerabilities,　where　attackers　mislead　the　behaviors　of　networking　systems　that　exploit　inter-device　coordination　to　execute　in-network　functions.　We　implement　20　existing　networking　systems　on　Tofino-based　switches　and　a　simulator,　and　attack　these　systems　with　the　identified　attacks.　The　experimental　results　indicate　that　our　attacks　significantly　interfere　with　the　normal　operations　of　the　selected　networking　systems,　e.g.,　the　cache　hit　rate　of　NetCache　drops　38%.　Our　analysis　also　demonstrates　that　none　of　existing　methods　can　fully　mitigate　our　attacks　since　they　fail　to　verify　the　packets　for　inter-device　coordination.　©　2023　IEEE.