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CVE-2026-58264 (GCVE-0-2026-58264)

Vulnerability from cvelistv5 – Published: 2026-09-18 19:59 – Updated: 2026-09-18 19:59
VLAI
Title
FluidSynth: Heap-based buffer overrun
Summary
FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 1.1.2 until 2.5.6, the FluidSynth command handler accepts a pitch_bend_range command whose channel argument is not bounds checked before the supplied value is written through the selected synth channel. An out-of-range channel can therefore cause an out-of-bounds heap write, leading to denial of service or possible code execution. The issue is remotely reachable when the TCP server is enabled through new_fluid_server() or fluidsynth -s, and it is locally reachable through malicious commands delivered to the FluidSynth shell on standard input. Applications that do not use the shell, command handler, or TCP server are not affected. This issue is fixed in version 2.5.6.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-122 - Heap-based Buffer Overflow
Assigner
References
Impacted products
Vendor Product Version CPE status
FluidSynth fluidsynth Affected: >= 1.1.2, < 2.5.6
guessed Create a notification for this product.
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{
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        }
      ],
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      "providerMetadata": {
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      },
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          "tags": [
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          "url": "https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6"
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      ],
      "source": {
        "advisory": "GHSA-mqmq-w63q-cj94",
        "discovery": "UNKNOWN"
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      "title": "FluidSynth: Heap-based buffer overrun"
    }
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  "cveMetadata": {
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    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-58264",
    "datePublished": "2026-09-18T19:59:39.880Z",
    "dateReserved": "2026-06-29T21:54:30.331Z",
    "dateUpdated": "2026-09-18T19:59:39.880Z",
    "state": "PUBLISHED"
  },
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                  }
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        ],
        "cveTags": [],
        "descriptions": [
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            "value": "FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 1.1.2 until 2.5.6, the FluidSynth command handler accepts a pitch_bend_range command whose channel argument is not bounds checked before the supplied value is written through the selected synth channel. An out-of-range channel can therefore cause an out-of-bounds heap write, leading to denial of service or possible code execution. The issue is remotely reachable when the TCP server is enabled through new_fluid_server() or fluidsynth -s, and it is locally reachable through malicious commands delivered to the FluidSynth shell on standard input. Applications that do not use the shell, command handler, or TCP server are not affected. This issue is fixed in version 2.5.6."
          }
        ],
        "id": "CVE-2026-58264",
        "lastModified": "2026-09-18T20:17:18.107",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
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            "url": "https://github.com/FluidSynth/fluidsynth/pull/1796"
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          {
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        "vulnStatus": "Received",
        "weaknesses": [
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                "value": "CWE-122"
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            "source": "security-advisories@github.com",
            "type": "Primary"
          }
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      }
    }
  }
}



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