CVE-2026-61721Hinoki check available

Memory disclosure and interruption via unchecked DLS loops

Published Sep 18, 2026 · Updated Sep 18, 2026

Out-of-bounds reads in FluidSynth 2.5.0 through 2.5.5 allow local users to disclose memory or interrupt audio rendering via DLS files. The native DLS loader copies file-controlled wsmp.loop_start and wsmp.loop_length into sample loop points without validating or sanitizing them, permitting loops beyond the sample buffer. Exposure requires a build with enable-native-dls enabled and processing of a crafted DLS file; rendering can read adjacent memory or deny service.

CVSS severity8.0
High
EPSS probability0.19%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Out-of-bounds reads in FluidSynth 2.5.0 through 2.5.5 allow local users to disclose memory or interrupt audio rendering via DLS files. The native DLS loader copies file-controlled wsmp.loop_start and wsmp.loop_length into sample loop points without validating or sanitizing them, permitting loops beyond the sample buffer. Exposure requires a build with enable-native-dls enabled and processing of a crafted DLS file; rendering can read adjacent memory or deny service.

The record

CVE
CVE-2026-61721
Published
Sep 18, 2026
Updated
Sep 18, 2026
Vendor
FluidSynth
Product
FluidSynth
Classifications
CWE-122, CWE-125
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

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Is a vulnerable build present?

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

  1. Affected versionversion=>= 2.5.0, < 2.5.6

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

FluidSynth · FluidSynthversion=>= 2.5.0, < 2.5.6

Published CVSS scores

8.0GitHub CNACVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:L/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-122Heap-based Buffer Overflow
CWE-125Out-of-bounds Read

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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