CVE-2026-61723

FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the native DLS parser validates ptbl chunks with the unsigned expression cues * 4 + cbsize without checking whether the multiplication and addition fit in 32 bits. A crafted DLS file can supply a large cues value that wraps the expression and passes the chunk-size check, causing poolcues.resize(cues) to request approximately four gigabytes and the parser to read billions of entries beyond the chunk boundary. The excessive allocation and invalid reads can cause denial of service. Builds with enable-native-dls set to OFF are not exposed. This issue is fixed in version 2.5.6.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.5 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FluidSynth/fluidsynth/commit/a2ab32b9c3b9f8845b7254adea73c211f6c5a24c
https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6
https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-r4mc-v3p8-pv47

Configurations

No configuration.

History

18 Sep 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 20:17

Updated : 2026-09-24 21:25

NVD link : CVE-2026-61723

Mitre link : CVE-2026-61723

CVE.ORG link : CVE-2026-61723

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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