FKIE_CVE-2026-61722

Vulnerability from fkie_nvd - Published: 2026-09-18 20:17 - Updated: 2026-09-23 18:28
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 articulation chunks using the unsigned expression cbsize + connblocks * 12 without first ensuring that the multiplication and addition fit in 32 bits. A crafted DLS file can supply a large connblocks value that wraps the expression and bypasses the chunk-size check, after which the parser performs approximately one billion 12-byte iterations beyond the chunk boundary. The excessive processing and invalid reads can cause denial of service. Builds with the CMake option enable-native-dls set to OFF do not expose the parser. This issue is fixed in version 2.5.6.
References
security-advisories@github.comhttps://github.com/FluidSynth/fluidsynth/commit/4d7084fca7c876f5d738498b4917a39faf603425
security-advisories@github.comhttps://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6
security-advisories@github.comhttps://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-hp72-35pr-6h6r
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 articulation chunks using the unsigned expression cbsize + connblocks * 12 without first ensuring that the multiplication and addition fit in 32 bits. A crafted DLS file can supply a large connblocks value that wraps the expression and bypasses the chunk-size check, after which the parser performs approximately one billion 12-byte iterations beyond the chunk boundary. The excessive processing and invalid reads can cause denial of service. Builds with the CMake option enable-native-dls set to OFF do not expose the parser. This issue is fixed in version 2.5.6."
    }
  ],
  "id": "CVE-2026-61722",
  "lastModified": "2026-09-23T18:28:25.093",
  "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-2026-61722",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-22T15:43:44.365934Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-18T20:17:18.713",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/FluidSynth/fluidsynth/commit/4d7084fca7c876f5d738498b4917a39faf603425"
    },
    {
      "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-hp72-35pr-6h6r"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-190"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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