CVE-2026-61721

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.

CVSS v3 8.0 HIGH

8.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.5 / Impact : 5.5

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FluidSynth/fluidsynth/commit/2354c2a9acdb26de7cdcd37c903ee108f46c0a7d
https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6
https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-59ph-rx8r-8p4j

Configurations

No configuration.

History

18 Sep 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 20:17

Updated : 2026-09-23 18:12

NVD link : CVE-2026-61721

Mitre link : CVE-2026-61721

CVE.ORG link : CVE-2026-61721

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

CWE-125

Out-of-bounds Read

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