CVE-2026-61714

Memory corruption via oversized MIDI channel configuration

Published Sep 18, 2026 · Updated Sep 18, 2026

Heap buffer overflow in FluidSynth 2.2.4 through 2.5.5 allows local users to corrupt memory through a MIDI channel count above 16. MIDI-player routines index the fixed-size channel_isplaying heap array using configured channel counts or unconstrained event channels instead of limiting indexes to 16 entries. User interaction and a nondefault synth.midi-channels value above 16 are required; the resulting undefined behavior can disclose or modify memory or crash the process.

CVSS severity7.8
High
EPSS probability0.14%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Get started

Summary

What happened

Heap buffer overflow in FluidSynth 2.2.4 through 2.5.5 allows local users to corrupt memory through a MIDI channel count above 16. MIDI-player routines index the fixed-size channel_isplaying heap array using configured channel counts or unconstrained event channels instead of limiting indexes to 16 entries. User interaction and a nondefault synth.midi-channels value above 16 are required; the resulting undefined behavior can disclose or modify memory or crash the process.

The record

CVE
CVE-2026-61714
Published
Sep 18, 2026
Updated
Sep 18, 2026
Vendor
FluidSynth
Product
FluidSynth
Classifications
CWE-787, CWE-125, CWE-122
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 18, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 2.2.4, < 2.5.6

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

FluidSynth · FluidSynthversion=>= 2.2.4, < 2.5.6

Published CVSS scores

7.8GitHubCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-125Out-of-bounds Read
CWE-122Heap-based Buffer Overflow

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Get started to see how Hinoki identifies affected software and validates exploitability in your environment.

Get started