CVE-2026-111123

FluidSynth through 2.6.1 contains an out-of-bounds write vulnerability that allows attackers to corrupt heap and stack memory by supplying unvalidated SoundFont modulator destination values. Attackers can craft an SF2 file with PMOD/IMOD destinations of 63 to 255 that, when loaded and played, write past the voice generator array and updated_gen_bit, causing memory corruption and crashes.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FluidSynth/fluidsynth
https://github.com/FluidSynth/fluidsynth/blob/71e85b2ca6bf48641ba7e2261d8f2640ae473773/src/sfloader/fluid_defsfont.c#L1609-L1611
https://github.com/FluidSynth/fluidsynth/blob/71e85b2ca6bf48641ba7e2261d8f2640ae473773/src/synth/fluid_voice.c#L1184-L1229
https://github.com/FluidSynth/fluidsynth/blob/71e85b2ca6bf48641ba7e2261d8f2640ae473773/src/synth/fluid_voice.c#L615-L623
https://hackmd.io/@haind-pwn/fluidsynth-sf2-modulator-dest-generator-oob-write
https://www.vulncheck.com/advisories/fluidsynth-through-2.6.1-out-of-bounds-write-via-soundfont-modulator-destination
https://hackmd.io/@haind-pwn/fluidsynth-sf2-modulator-dest-generator-oob-write

Configurations

No configuration.

History

15 Oct 2026, 20:17

Type	Values Removed	Values Added
References	~~() https://hackmd.io/@haind-pwn/fluidsynth-sf2-modulator-dest-generator-oob-write -~~	() https://hackmd.io/@haind-pwn/fluidsynth-sf2-modulator-dest-generator-oob-write -

15 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 19:17

Updated : 2026-10-15 20:17

NVD link : CVE-2026-111123

Mitre link : CVE-2026-111123

CVE.ORG link : CVE-2026-111123

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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