Vulnerability-Lookup

OESA-2026-2961 (CVE-2026-58264)

Vulnerability from osv_openeuler – Published: 2026-07-09 11:11 – Updated: 2026-08-06 11:11 – Source website

Summary

fluidsynth security update

Details

FluidSynth is a free software synthesizer. Its currently based on the SoundFont 2 specifications and supports real time MIDI effect controls. It can be used as a shared library for embedding in other applications, can play MIDI files and has a command line shell. Many other applications use FluidSynth for audio synthesis.

Security Fix(es):

A heap-based buffer overrun was discovered in fluidsynth's command handler. Sending a pitch_bend_range command to the handler with an out-of-bounds channel argument will attempt to write the provided value argument into heap memory. If the command handler is exposed via fluidsynth's TCP server (i.e. created via new_fluid_server() or via fluidsynth -s) an attacker may manipulate heap memory, causing denial of service or remote code execution.(CVE-2026-58264)

Severity

9.8 (Critical)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

URL

Type

	https://www.openeuler.org/zh/security/security-bu…	ADVISORY
	https://nvd.nist.gov/vuln/detail/CVE-2026-58264	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "aarch64": [
          "fluidsynth-2.3.4-3.oe2403sp3.aarch64.rpm",
          "fluidsynth-debuginfo-2.3.4-3.oe2403sp3.aarch64.rpm",
          "fluidsynth-debugsource-2.3.4-3.oe2403sp3.aarch64.rpm",
          "fluidsynth-devel-2.3.4-3.oe2403sp3.aarch64.rpm",
          "fluidsynth-help-2.3.4-3.oe2403sp3.aarch64.rpm"
        ],
        "src": [
          "fluidsynth-2.3.4-3.oe2403sp3.src.rpm"
        ],
        "x86_64": [
          "fluidsynth-2.3.4-3.oe2403sp3.x86_64.rpm",
          "fluidsynth-debuginfo-2.3.4-3.oe2403sp3.x86_64.rpm",
          "fluidsynth-debugsource-2.3.4-3.oe2403sp3.x86_64.rpm",
          "fluidsynth-devel-2.3.4-3.oe2403sp3.x86_64.rpm",
          "fluidsynth-help-2.3.4-3.oe2403sp3.x86_64.rpm"
        ]
      },
      "package": {
        "ecosystem": "openEuler:24.03-LTS-SP3",
        "name": "fluidsynth",
        "purl": "pkg:rpm/openEuler/fluidsynth\u0026distro=openEuler-24.03-LTS-SP3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.3.4-3.oe2403sp3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "severity": "Critical"
  },
  "details": "FluidSynth is a free software synthesizer. Its currently based on the SoundFont 2 specifications and supports real time MIDI effect controls. It can be used as a shared library for embedding in other applications, can play MIDI files and has a command line shell. Many other applications use FluidSynth for audio synthesis.\r\n\r\nSecurity Fix(es):\n\nA heap-based buffer overrun was discovered in fluidsynth\u0026apos;s command handler. Sending a `pitch_bend_range` command to the handler with an out-of-bounds `channel` argument will attempt to write the provided `value` argument into heap memory. If the command handler is exposed via fluidsynth\u0026apos;s TCP server (i.e. created via `new_fluid_server()` or via `fluidsynth -s`) an attacker may manipulate heap memory, causing denial of service or remote code execution.(CVE-2026-58264)",
  "id": "OESA-2026-2961",
  "modified": "2026-08-06T11:11:51Z",
  "published": "2026-07-09T11:11:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2961"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-58264"
    }
  ],
  "schema_version": "1.7.2",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "fluidsynth security update",
  "upstream": [
    "CVE-2026-58264"
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-09-18 19:59 – Updated: 2026-09-21 20:47

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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-21 20:44 UTC

CWE

CWE-122 - Heap-based Buffer Overflow

Assigner

GitHub_M CNA under the mitre root

CNA scorecard C 72/100 over 7820 records in the last 180 days details

References

4 references

URL	Tags
https://github.com/FluidSynth/fluidsynth/security…	x_refsource_CONFIRM
https://github.com/FluidSynth/fluidsynth/pull/1796	x_refsource_MISC
https://github.com/FluidSynth/fluidsynth/commit/7…	x_refsource_MISC
https://github.com/FluidSynth/fluidsynth/releases…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
FluidSynth	fluidsynth	Affected: >= 1.1.2, < 2.5.6

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-58264",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-21T20:44:11.157258Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-21T20:47:56.341Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "fluidsynth",
          "vendor": "FluidSynth",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 1.1.2, \u003c 2.5.6"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "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."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-122",
              "description": "CWE-122: Heap-based Buffer Overflow",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-18T19:59:39.880Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-mqmq-w63q-cj94",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/FluidSynth/fluidsynth/security/advisories/GHSA-mqmq-w63q-cj94"
        },
        {
          "name": "https://github.com/FluidSynth/fluidsynth/pull/1796",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/FluidSynth/fluidsynth/pull/1796"
        },
        {
          "name": "https://github.com/FluidSynth/fluidsynth/commit/762a3bd39a431cd45abf3bbcce7286c87909d087",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/FluidSynth/fluidsynth/commit/762a3bd39a431cd45abf3bbcce7286c87909d087"
        },
        {
          "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-mqmq-w63q-cj94",
        "discovery": "UNKNOWN"
      },
      "title": "FluidSynth: Heap-based buffer overrun"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-58264",
    "datePublished": "2026-09-18T19:59:39.880Z",
    "dateReserved": "2026-06-29T21:54:30.331Z",
    "dateUpdated": "2026-09-21T20:47:56.341Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

Action not permitted