Vulnerability Description
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 Score
MEDIUM
Related Weaknesses (CWE)
References
- https://github.com/FluidSynth/fluidsynth/commit/a2ab32b9c3b9f8845b7254adea73c211
- https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6
- https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-r4mc-v3p8-pv47
FAQ
What is CVE-2026-61723?
CVE-2026-61723 is a vulnerability with a CVSS score of 6.8 (MEDIUM). 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...
How severe is CVE-2026-61723?
CVE-2026-61723 has been rated MEDIUM with a CVSS base score of 6.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-61723?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.