CVE-2026-61722 (GCVE-0-2026-61722)

Vulnerability from cvelistv5 – Published: 2026-09-18 20:01 – Updated: 2026-09-22 15:44
VLAI
Title
FluidSynth: DLS Articulation Chunk Integer Overflow
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.
Severity
6.8 (Medium)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-22 15:43 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
References
Impacted products
Vendor Product Version CPE status
FluidSynth fluidsynth Affected: >= 2.5.0, < 2.5.6
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-61722",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-22T15:43:44.365934Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-22T15:44:05.935Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "fluidsynth",
          "vendor": "FluidSynth",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 2.5.0, \u003c 2.5.6"
            }
          ]
        }
      ],
      "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "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"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-190",
              "description": "CWE-190: Integer Overflow or Wraparound",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-18T20:01:58.603Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-hp72-35pr-6h6r",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-hp72-35pr-6h6r"
        },
        {
          "name": "https://github.com/FluidSynth/fluidsynth/commit/4d7084fca7c876f5d738498b4917a39faf603425",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/FluidSynth/fluidsynth/commit/4d7084fca7c876f5d738498b4917a39faf603425"
        },
        {
          "name": "https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/FluidSynth/fluidsynth/releases/tag/v2.5.6"
        }
      ],
      "source": {
        "advisory": "GHSA-hp72-35pr-6h6r",
        "discovery": "UNKNOWN"
      },
      "title": "FluidSynth: DLS Articulation Chunk Integer Overflow"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-61722",
    "datePublished": "2026-09-18T20:01:58.603Z",
    "dateReserved": "2026-07-10T18:51:13.921Z",
    "dateUpdated": "2026-09-22T15:44:05.935Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-61722",
      "date": "2026-09-23",
      "epss": "0.00154",
      "percentile": "0.04867"
    },
    "nvd": {
      "cve": {
        "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"
          }
        ]
      }
    },
    "redhat_vex": {
      "current_release_date": "2026-09-23T09:02:56+00:00",
      "cve": "CVE-2026-61722",
      "id": "CVE-2026-61722",
      "initial_release_date": "2026-09-18T20:01:58.603000+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "FluidSynth: FluidSynth: Denial of Service via DLS Articulation Chunk Integer Overflow",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-61722.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.