Furnace through 0.6.8.3 contains an out-of-bounds heap read vulnerability in DivEngine::loadFTM() in src/engine/fileOps/ftm.cpp, triggered by an unbounded DPCM note count during FamiTracker module import. Attackers can craft a .ftm, .dnm or 0CC/E-FamiTracker module with a 2A03 instrument note count above 120 to read past the noteMap array and crash Furnace when opened.

Furnace through 0.6.8.3 contains an out-of-bounds write vulnerability in DivEngine::loadFTM() that allows attackers to corrupt heap memory via an unchecked subsong index in the GROOVES block. Attackers can craft a FamiTracker module with a subsong count of 2 or more to write a groove pattern past the subsong vector, crashing Furnace when opened.