{"id":"CVE-2026-61714","summary":"FluidSynth: Heap Buffer Overflow in MIDI Player","details":"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.","aliases":["GHSA-976m-35rw-h3m6"],"modified":"2026-09-20T11:46:52.030575035Z","published":"2026-09-18T20:01:14.342Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-122","CWE-125","CWE-787"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/61xxx/CVE-2026-61714.json"},"references":[{"type":"WEB","url":"https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/61xxx/CVE-2026-61714.json"},{"type":"ADVISORY","url":"https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-976m-35rw-h3m6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-61714"},{"type":"FIX","url":"https://github.com/FluidSynth/fluidsynth/commit/772702e00cc6acc7c607efb40283e2269211effc"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/fluidsynth/fluidsynth","events":[{"introduced":"6c807bdd37748411801e93c48fcd5789d5a6a278"},{"fixed":"772702e00cc6acc7c607efb40283e2269211effc"},{"fixed":"e5b11058a619246cea42976dacb76ca54be3d45d"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"2.2.4"},{"fixed":"2.5.6"}]}}],"versions":["v2.5.5","v2.5.4","v2.5.3","v2.5.2","v2.5.1","v2.5.0","v2.4.6","v2.4.5","v2.4.4","v2.4.3","v2.4.2","v2.4.1","v2.4.0","v2.3.4","v2.3.3","v2.3.2","v2.3.1","v2.3.0","v2.2.4"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-61714.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"}]}