Espruino before 1.99 allows attackers to cause a denial of service (application crash) and potential Information Disclosure with a user crafted input file via a Buffer Overflow during syntax parsing because strncpy is misused in jslex.c.
https://github.com/espruino/Espruino/issues/1426
https://github.com/espruino/Espruino/files/2019228/eh_0.txt
https://github.com/espruino/Espruino/commit/bed844f109b6c222816740555068de2e101e8018