CVE-2026-61721

high

Description

FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the native DLS loader assigns file-controlled wsmp.loop_start and wsmp.loop_length values to samples without calling fluid_sample_validate() or fluid_sample_sanitize_loop(). A crafted DLS file can place sample loop points beyond the sample buffer, causing out-of-bounds reads during audio rendering, undefined behavior, possible memory disclosure, and denial of service. Builds compiled with the CMake option enable-native-dls set to OFF do not expose the affected parser. This issue is fixed in version 2.5.6.

References

https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-59ph-rx8r-8p4j

https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6

https://github.com/FluidSynth/fluidsynth/commit/2354c2a9acdb26de7cdcd37c903ee108f46c0a7d

Details

Source: Mitre, NVD

Published: 2026-09-18

Updated: 2026-09-18

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:P/A:C

Severity: Medium

CVSS v3

Base Score: 8

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H

Severity: High

EPSS

EPSS: 0.00149