CVE-2026-111123 (GCVE-0-2026-111123)
Vulnerability from cvelistv5 – Published: 2026-10-15 18:57 – Updated: 2026-10-15 19:46
VLAI
EPSS
VEX
Title
FluidSynth through 2.6.1 Out-of-Bounds Write via SoundFont Modulator Destination
Summary
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.
Severity
6.1 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-15 19:46 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
6 references
| URL | Tags |
|---|---|
| https://hackmd.io/@haind-pwn/fluidsynth-sf2-modul… | technical-description |
| https://github.com/FluidSynth/fluidsynth/blob/71e… | technical-description |
| https://github.com/FluidSynth/fluidsynth/blob/71e… | technical-description |
| https://github.com/FluidSynth/fluidsynth/blob/71e… | technical-description |
| https://github.com/FluidSynth/fluidsynth | product |
| https://www.vulncheck.com/advisories/fluidsynth-t… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| FluidSynth | fluidsynth |
Affected:
0 , ≤ 2.6.1
(semver)
cpe:2.3:a:fluidsynth:fluidsynth:*:*:*:*:*:*:*:* |
Date Public
2026-10-15 00:00
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