6.8
MEDIUM CVSS 3.1
CVE-2026-61723
FluidSynth: DLS ptbl Chunk Integer Overflow
Description

FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the native DLS parser validates ptbl chunks with the unsigned expression cues * 4 + cbsize without checking whether the multiplication and addition fit in 32 bits. A crafted DLS file can supply a large cues value that wraps the expression and passes the chunk-size check, causing poolcues.resize(cues) to request approximately four gigabytes and the parser to read billions of entries beyond the chunk boundary. The excessive allocation and invalid reads can cause denial of service. Builds with enable-native-dls set to OFF are not exposed. This issue is fixed in version 2.5.6.

INFO

Published Date :

Sept. 18, 2026, 8:17 p.m.

Last Modified :

Sept. 18, 2026, 8:17 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-61723 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update FluidSynth to version 2.5.6 or later to fix denial of service vulnerability.
  • Update FluidSynth to version 2.5.6 or later.
  • Disable native DLS parsing if updating is not possible.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-61723.

URL Resource
https://github.com/FluidSynth/fluidsynth/commit/a2ab32b9c3b9f8845b7254adea73c211f6c5a24c
https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6
https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-r4mc-v3p8-pv47
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-61723 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-61723 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-61723 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-61723 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 18, 2026

    Action Type Old Value New Value
    Added Description FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the native DLS parser validates ptbl chunks with the unsigned expression cues * 4 + cbsize without checking whether the multiplication and addition fit in 32 bits. A crafted DLS file can supply a large cues value that wraps the expression and passes the chunk-size check, causing poolcues.resize(cues) to request approximately four gigabytes and the parser to read billions of entries beyond the chunk boundary. The excessive allocation and invalid reads can cause denial of service. Builds with enable-native-dls set to OFF are not exposed. This issue is fixed in version 2.5.6.
    Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
    Added CWE CWE-190
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/61xxx/CVE-2026-61723.json">CVE-2026-61723</a>
    Added Reference https://github.com/FluidSynth/fluidsynth/commit/a2ab32b9c3b9f8845b7254adea73c211f6c5a24c
    Added Reference https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6
    Added Reference https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-r4mc-v3p8-pv47
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.