CVE-2025-68617

7.0 HIGH
Published: December 23, 2025 Modified: January 15, 2026
View on NVD

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.

AI Explanation

Get an AI-powered plain-language explanation of this vulnerability and remediation steps.

Login to generate AI explanation

CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/FluidSynth/fluidsynth/issues/1717
Source: security-advisories@github.com
Exploit Issue Tracking
https://github.com/FluidSynth/fluidsynth/issues/1728
Source: security-advisories@github.com
Issue Tracking
https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-ffw2-xvvp-39ch
Source: security-advisories@github.com
Vendor Advisory
https://github.com/FluidSynth/fluidsynth/issues/1717
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
Exploit Issue Tracking
https://github.com/FluidSynth/fluidsynth/issues/1728
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
Issue Tracking

7 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.0 / 10.0
EPSS (Exploit Probability)
0.0%
5th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

fluidsynth