{"id":"UBUNTU-CVE-2026-61714","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.","modified":"2026-10-06T23:31:50.841973478Z","published":"2026-09-18T20:17:00Z","related":["USN-8885-1"],"upstream":["CVE-2026-61714"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-61714"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-61714"},{"type":"REPORT","url":"https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-976m-35rw-h3m6"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8885-1"}],"affected":[{"package":{"name":"fluidsynth","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/fluidsynth?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.5-1ubuntu0.1~esm1"}]}],"versions":["2.1.7-1.1","2.2.4-2","2.2.5-1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro","binaries":[{"binary_name":"fluidsynth","binary_version":"2.2.5-1ubuntu0.1~esm1"},{"binary_name":"libfluidsynth3","binary_version":"2.2.5-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61714.json"}},{"package":{"name":"fluidsynth","ecosystem":"Ubuntu:Pro:24.04:LTS","purl":"pkg:deb/ubuntu/fluidsynth?arch=source&distro=esm-apps%2Fnoble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.3.4-1ubuntu0.1~esm1"}]}],"versions":["2.3.3-2.1","2.3.4-1","2.3.4-1build1","2.3.4-1build2","2.3.4-1build3"],"ecosystem_specific":{"binaries":[{"binary_version":"2.3.4-1ubuntu0.1~esm1","binary_name":"fluidsynth"},{"binary_version":"2.3.4-1ubuntu0.1~esm1","binary_name":"libfluidsynth3"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-61714.json"}},{"package":{"name":"fluidsynth","ecosystem":"Ubuntu:Pro:26.04:LTS","purl":"pkg:deb/ubuntu/fluidsynth?arch=source&distro=esm-apps%2Fresolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.4.8+dfsg-1ubuntu0.1~esm1"}]}],"versions":["2.4.7+dfsg-2","2.4.8+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"fluidsynth","binary_version":"2.4.8+dfsg-1ubuntu0.1~esm1"},{"binary_version":"2.4.8+dfsg-1ubuntu0.1~esm1","binary_name":"libfluidsynth3"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-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"},{"type":"Ubuntu","score":"medium"}]}