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.
References3
Metrics
- CVSS 3.1
-
8.0
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H - EPSS — exploit probability
- 0% percentile: 9 · as of 8 November 2026
- CWE
- CWE-122CWE-125
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