CVE-2026-61722
mediumFluidSynth is a software synthesizer based on the SoundFont 2 specifications.
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 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.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/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/4d7084fca7c876f5d738498b4917a39faf603425 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-hp72-35pr-6h6r security-advisories@github.com