CVE-2026-61714
highFluidSynth is a software synthesizer based on the SoundFont 2 specifications.
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 2.5.6.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/FluidSynth/fluidsynth/commit/772702e00cc6acc7c607efb40283e2269211effc security-advisories@github.com
- https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6 security-advisories@github.com
- https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-976m-35rw-h3m6 security-advisories@github.com