{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-61720","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-07-10T18:51:13.920Z","datePublished":"2026-09-18T20:03:43.989Z","dateUpdated":"2026-09-21T16:27:25.573Z"},"containers":{"cna":{"title":"FluidSynth: SF2 DMOD Chunk Unsigned Underflow","problemTypes":[{"descriptions":[{"cweId":"CWE-191","lang":"en","description":"CWE-191: Integer Underflow (Wrap or Wraparound)","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"LOCAL","availabilityImpact":"HIGH","baseScore":6.2,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"name":"https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-rmc4-c8hw-455w","tags":["x_refsource_CONFIRM"],"url":"https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-rmc4-c8hw-455w"},{"name":"https://github.com/FluidSynth/fluidsynth/commit/096e1ff0d09ddcac83d94923440706f76f94bc44","tags":["x_refsource_MISC"],"url":"https://github.com/FluidSynth/fluidsynth/commit/096e1ff0d09ddcac83d94923440706f76f94bc44"},{"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"}],"affected":[{"vendor":"FluidSynth","product":"fluidsynth","versions":[{"version":">= 2.5.0, < 2.5.6","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-09-18T20:03:43.989Z"},"descriptions":[{"lang":"en","value":"FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the SF2 parser computes the DMOD modulator count as chunk.size / SF_MOD_SIZE - 1 without rejecting chunks smaller than one record. A crafted SF2 file containing a zero-sized DMOD chunk makes the unsigned subtraction wrap to UINT_MAX, and the parser then attempts billions of SFMod allocations. This exhausts process memory and causes denial of service. No workaround is available. This issue is fixed in version 2.5.6."}],"source":{"advisory":"GHSA-rmc4-c8hw-455w","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-21T16:27:05.665077Z","id":"CVE-2026-61720","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-21T16:27:25.573Z"}}]}}