FKIE_CVE-2026-61723

Vulnerability from fkie_nvd - Published: 2026-09-18 20:17 - Updated: 2026-09-24 21:25
Severity
6.8 (Medium) - CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Summary
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.
References
security-advisories@github.comhttps://github.com/FluidSynth/fluidsynth/commit/a2ab32b9c3b9f8845b7254adea73c211f6c5a24c
security-advisories@github.comhttps://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6
security-advisories@github.comhttps://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-r4mc-v3p8-pv47
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "fluidsynth",
          "vendor": "FluidSynth",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 2.5.0, \u003c 2.5.6"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-61723",
  "lastModified": "2026-09-24T21:25:27.050",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 4.2,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-61723",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-21T19:40:11.237880Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-18T20:17:18.853",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/FluidSynth/fluidsynth/commit/a2ab32b9c3b9f8845b7254adea73c211f6c5a24c"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-r4mc-v3p8-pv47"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-190"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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