gpsd before commit dc966aa contains a heap-based out-of-bounds write vulnerability in the drivers/driver_nmea2000.c file. The hnd_129540 function, which handles NMEA2000 PGN 129540 (GNSS Satellites in View) packets, fails to validate the user-supplied satellite count against the size of the skyview array (184 elements). This allows an attacker to write beyond the bounds of the array by providing a satellite count up to 255, leading to memory corruption, Denial of Service (DoS), and potentially arbitrary code execution.