Secuno
ENNL
Book demo

CVE-2025-68617

Fluidsynth use-after-free

7.0 HIGHPublic exploitEPSS 0.21%
  1. Published23 Dec 2025

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 3.1 breakdown

Attack vectorLocal
Attack complexityHigh
Privileges requiredNone
User interactionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

Fluidsynth≥ 2.5.0 < 2.5.2

Remediation

Fixed in
Fluidsynth≥ 2.5.2

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

CVE-2026-859658.0
Progress MarkLogic Server 12.x releases before 12.1.0 and 11.x releases before 11.3.7…
CVE-2026-57599.8
A double free and use-after-free vulnerability in the RdbLoadDeletedNodes function of…
CVE-2026-1071838.1
llama.cpp before b11393 contains a use-after-free and double free vulnerability in…
CVE-2026-553309.8
In BluetoothCccHandlerCallbackImpl of bluetooth_ccc.cc, there is a possible…
CVE-2026-1064238.8
Use after free in Media in Google Chrome prior to 155.0.8059.39 allowed a remote…
CVE-2026-1064218.8
Use after free in PDF in Google Chrome prior to 155.0.8059.39 allowed a remote attacker…

Frequently asked

Is CVE-2025-68617 being actively exploited?

CVE-2025-68617 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.21%.

How severe is CVE-2025-68617?

CVE-2025-68617 has a CVSS 3.1 base score of 7.0, rated high. EPSS estimates a 0.21% probability of exploitation.

Which products are affected by CVE-2025-68617?

Affected products include Fluidsynth.

How do I fix CVE-2025-68617?

Upgrade affected software to a fixed version, for example Fluidsynth 2.5.2 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2025-68617 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation worksBook a demo

Get Patch this first every Monday

Five vulnerabilities that matter this week, ranked on real exploitation. Plain language, one email, no spam.

You can unsubscribe with one click from every issue. We handle your details as described in our privacy policy.

Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.