{"id":"CVE-2026-61722","title":"FluidSynth is a software synthesizer based on the SoundFont 2 specifications","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 …","severity":"medium","cvss":6.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","cwe":["CWE-190"],"vendor":"FluidSynth","product":"fluidsynth","affected":["fluidsynth >= 2.5.0, < 2.5.6"],"published":"2026-09-18","updated":"2026-09-18","sourceUpdated":"2026-09-18T20:17:18.713","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-61722","references":[{"url":"https://github.com/FluidSynth/fluidsynth/commit/4d7084fca7c876f5d738498b4917a39faf603425","label":"security-advisories@github.com"},{"url":"https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6","label":"security-advisories@github.com"},{"url":"https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-hp72-35pr-6h6r","label":"security-advisories@github.com"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-18T20:51:25.675Z","epss":0.00154,"epssPercentile":0.04857,"slug":"CVE-2026-61722","body":"## Overview\n\nFluidSynth 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 boundary. The excessive processing and invalid reads can cause denial of service. Builds with the CMake option enable-native-dls set to OFF do not expose the parser. This issue is fixed in version 2.5.6.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":37,"depthScoreParts":{"impact":37.4,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}