| Name | CVE-2025-68617 |
| 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 1123964 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| fluidsynth (PTS) | bullseye | 2.1.7-1.1 | fixed |
| bookworm | 2.3.1-2 | fixed | |
| trixie | 2.4.4+dfsg-1+deb13u1 | fixed | |
| forky, sid | 2.5.2+dfsg-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| fluidsynth | source | bullseye | (not affected) | |||
| fluidsynth | source | bookworm | (not affected) | |||
| fluidsynth | source | trixie | (not affected) | |||
| fluidsynth | source | (unstable) | 2.5.2+dfsg-1 | 1123964 |
[trixie] - fluidsynth <not-affected> (Vulnerable code adding native DLS support introduced later)
[bookworm] - fluidsynth <not-affected> (Vulnerable code adding native DLS support introduced later)
[bullseye] - fluidsynth <not-affected> (Native DLS support was added later)
https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-ffw2-xvvp-39ch
https://github.com/FluidSynth/fluidsynth/issues/1717
https://github.com/FluidSynth/fluidsynth/issues/1728
Fixed by: https://github.com/FluidSynth/fluidsynth/commit/92f81cb3b8e02dcb78888bd4dfb9e61076c33c34 (v2.5.2)
Fixed by: https://github.com/FluidSynth/fluidsynth/commit/ca2f65dcfaff7f69e5bb9fee311798a6a35443e0 (v2.5.2)
Fixed by: https://github.com/FluidSynth/fluidsynth/commit/962b9946b5cb6b16f0c08b89dd1b7016d4fce886 (v2.5.2)