FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the native DLS parser validates articulation chunks using the unsigned expression cbsize + connbl…

Summary

FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the native DLS parser validates articulation chunks using the unsigned expression cbsize + connblocks * 12 without first ensuring that the multiplication and addition fit in 32 bits. A crafted DLS file can supply a large connblocks value that wraps the expression and bypasses the chunk-size check, after which the parser performs approximately one billion 12-byte iterations beyond the chunk boun…