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GHSA-6875-67C4-4637

Vulnerability from github – Published: 2025-05-19 09:31 – Updated: 2025-11-17 21:31

Details

In the Linux kernel, the following vulnerability has been resolved:

ALSA: ump: Fix buffer overflow at UMP SysEx message conversion

The conversion function from MIDI 1.0 to UMP packet contains an internal buffer to keep the incoming MIDI bytes, and its size is 4, as it was supposed to be the max size for a MIDI1 UMP packet data. However, the implementation overlooked that SysEx is handled in a different format, and it can be up to 6 bytes, as found in do_convert_to_ump(). It leads eventually to a buffer overflow, and may corrupt the memory when a longer SysEx message is received.

The fix is simply to extend the buffer size to 6 to fit with the SysEx UMP message.

Severity

7.8 (High)


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

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{
  "affected": [],
  "aliases": [
    "CVE-2025-37891"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-120"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-19T08:15:21Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: ump: Fix buffer overflow at UMP SysEx message conversion\n\nThe conversion function from MIDI 1.0 to UMP packet contains an\ninternal buffer to keep the incoming MIDI bytes, and its size is 4, as\nit was supposed to be the max size for a MIDI1 UMP packet data.\nHowever, the implementation overlooked that SysEx is handled in a\ndifferent format, and it can be up to 6 bytes, as found in\ndo_convert_to_ump().  It leads eventually to a buffer overflow, and\nmay corrupt the memory when a longer SysEx message is received.\n\nThe fix is simply to extend the buffer size to 6 to fit with the SysEx\nUMP message.",
  "id": "GHSA-6875-67c4-4637",
  "modified": "2025-11-17T21:31:17Z",
  "published": "2025-05-19T09:31:08Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-37891"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/226beac5605afbb33f8782148d188b64396145a4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/42ef48dd4ebb082a1a90b5c3feeda2e68a9e32fe"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/56f1f30e6795b890463d9b20b11e576adf5a2f77"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ce4f77bef276e7d2eb7ab03a5d08bcbaa40710ec"
    }
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  "schema_version": "1.4.0",
  "severity": [
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      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2025-37891 (GCVE-0-2025-37891)

Vulnerability from cvelistv5 – Published: 2025-05-19 07:19 – Updated: 2026-10-15 21:52

Title

ALSA: ump: Fix buffer overflow at UMP SysEx message conversion

Summary

In the Linux kernel, the following vulnerability has been resolved: ALSA: ump: Fix buffer overflow at UMP SysEx message conversion The conversion function from MIDI 1.0 to UMP packet contains an internal buffer to keep the incoming MIDI bytes, and its size is 4, as it was supposed to be the max size for a MIDI1 UMP packet data. However, the implementation overlooked that SysEx is handled in a different format, and it can be up to 6 bytes, as found in do_convert_to_ump(). It leads eventually to a buffer overflow, and may corrupt the memory when a longer SysEx message is received. The fix is simply to extend the buffer size to 6 to fit with the SysEx UMP message.

Severity

7.8 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-15 21:45 UTC

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 7056 records in the last 180 days details

References

4 references

URL	Tags
https://git.kernel.org/stable/c/ce4f77bef276e7d2e…
https://git.kernel.org/stable/c/226beac5605afbb33…
https://git.kernel.org/stable/c/42ef48dd4ebb082a1…
https://git.kernel.org/stable/c/56f1f30e6795b8904…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 0b5288f5fe63eab687c14e5940b9e0d532b129f2 , < ce4f77bef276e7d2eb7ab03a5d08bcbaa40710ec (git) Affected: 0b5288f5fe63eab687c14e5940b9e0d532b129f2 , < 226beac5605afbb33f8782148d188b64396145a4 (git) Affected: 0b5288f5fe63eab687c14e5940b9e0d532b129f2 , < 42ef48dd4ebb082a1a90b5c3feeda2e68a9e32fe (git) Affected: 0b5288f5fe63eab687c14e5940b9e0d532b129f2 , < 56f1f30e6795b890463d9b20b11e576adf5a2f77 (git)
Linux	Linux	Affected: 6.5 Unaffected: 0 , < 6.5 (semver) Unaffected: 6.6.90 , ≤ 6.6.* (semver) Unaffected: 6.12.28 , ≤ 6.12.* (semver) Unaffected: 6.14.6 , ≤ 6.14.* (semver) Unaffected: 6.15 , ≤ * (original_commit_for_fix)

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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.

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