How severe is CVE-2025-68617?

CVE-2025-68617 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over local access with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-68617 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-68617?

CVE-2025-68617 affects Fluidsynth. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-68617?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-68617 have an EU (EUVD) identifier?

Yes. CVE-2025-68617 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-205027.

When was CVE-2025-68617 published?

CVE-2025-68617 was published on 2025-12-23 and last updated on 2026-06-17.

CVE-2025-68617

CVE-2025-68617 is a high-severity vulnerability in Fluidsynth with a CVSS 3.x base score of 7.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.

Key facts

Severity: High (CVSS 3.x base score 7.0)
EPSS exploit prediction: 0% (8th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-205027
Weakness: CWE-416
Affected product: Fluidsynth
Published: 2025-12-23
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2025-68617?: 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.
How severe is CVE-2025-68617?: CVE-2025-68617 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over local access with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-68617 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-68617?: CVE-2025-68617 affects Fluidsynth. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-68617?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-68617 have an EU (EUVD) identifier?: Yes. CVE-2025-68617 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-205027.
When was CVE-2025-68617 published?: CVE-2025-68617 was published on 2025-12-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fluidsynth:fluidsynth:*:*:*:*:*:*:*:*

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