Vulnerability Description
FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From versions 2.5.0 to before 2.5.2, a race condition during unloading of a DLS file can trigger a heap-based use-after-free. A concurrently running thread may be pending to unload a DLS file, leading to use of freed memory, if the synthesizer is being concurrently destroyed, or samples of the (unloaded) DLS file are concurrently used to synthesize audio. This issue has been patched in version 2.5.2. The problem will not occur, when explicitly unloading a DLS file (before synth destruction), provided that at the time of unloading, no samples of the respective file are used by active voices. The problem will not occur in versions of FluidSynth that have been compiled without native DLS support.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Fluidsynth | Fluidsynth | >= 2.5.0, < 2.5.2 |
Related Weaknesses (CWE)
References
- https://github.com/FluidSynth/fluidsynth/commit/685e54cdc44911ace31774260bd0c9ecPatch
- https://github.com/FluidSynth/fluidsynth/commit/962b9946b5cb6b16f0c08b89dd1b7016Patch
- https://github.com/FluidSynth/fluidsynth/issues/1717ExploitIssue Tracking
- https://github.com/FluidSynth/fluidsynth/issues/1728Issue Tracking
- https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-ffw2-xvvp-39chVendor Advisory
- https://github.com/FluidSynth/fluidsynth/issues/1717ExploitIssue Tracking
- https://github.com/FluidSynth/fluidsynth/issues/1728Issue Tracking
FAQ
What is CVE-2025-68617?
CVE-2025-68617 is a vulnerability with a CVSS score of 7.0 (HIGH). FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From versions 2.5.0 to before 2.5.2, a race condition during unloading of a DLS file can trigger a heap-based use-after-fr...
How severe is CVE-2025-68617?
CVE-2025-68617 has been rated HIGH with a CVSS base score of 7.0/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-68617?
Check the references section above for vendor advisories and patch information. Affected products include: Fluidsynth Fluidsynth.