Sicherheitslücken in fluidsynth

FluidSynth through 2.6.1 Out-of-Bounds Write via SoundFont Modulator Destination

FluidSynth through 2.6.1 contains an out-of-bounds write vulnerability that allows attackers to corrupt heap and stack memory by supplying unvalidated SoundFont modulator destination values. Attackers can craft an SF2 file with PMOD/IMOD destinations of 63 to 255 that, when loaded and played, write past the voice generator array and updated_gen_bit, causing memory corruption and crashes.

FluidSynth: Heap Buffer Overflow in MIDI Player

FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.2.4 until 2.5.6, configuring synth.midi-channels above 16 allows the MIDI player to index _fluid_player_t::channel_isplaying outside its fixed-size heap allocation while tracking active channels. The resulting out-of-bounds reads and writes invoke undefined behavior and may compromise confidentiality, integrity, or availability. No crafted MIDI file is required because the unsafe condition is created by the channel-count configuration itself. Keeping synth.midi-channels at its default value of 16 avoids the vulnerable path. This issue is fixed in version 2.5.

FluidSynth: Heap-based buffer overrun

FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 1.1.2 until 2.5.6, the FluidSynth command handler accepts a pitch_bend_range command whose channel argument is not bounds checked before the supplied value is written through the selected synth channel. An out-of-range channel can therefore cause an out-of-bounds heap write, leading to denial of service or possible code execution. The issue is remotely reachable when the TCP server is enabled through new_fluid_server() or fluidsynth -s, and it is locally reachable through malicious commands delivered to the FluidSynth shell on standard input. Applications that

CVE-2025-56225

fluidsynth-2.4.6 and earlier versions is vulnerable to Null pointer dereference in fluid_synth_monopoly.c, that can be triggered when loading an invalid midi file.

Use after free in fluidsynth

fluidsynth is a software synthesizer based on the SoundFont 2 specifications. A use after free violation was discovered in fluidsynth, that can be triggered when loading an invalid SoundFont file.

• Auf 2.1.7-1.1 aktualisieren