CVE-2025-37891

Published May 19, 2025

Last updated 5 months ago

CVSS high 7.8
Linux Kernel
ALSA

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-37891 is a buffer overflow vulnerability found in the Linux kernel's ALSA (Advanced Linux Sound Architecture) UMP (Universal MIDI Packet) subsystem. Specifically, the issue lies within the MIDI 1.0 to UMP packet conversion function. The internal buffer, intended to hold incoming MIDI bytes, is only 4 bytes in size. This buffer size is insufficient for handling SysEx messages, which can be up to 6 bytes long. Consequently, when a SysEx message exceeding 4 bytes is received, a buffer overflow occurs, potentially leading to memory corruption. A patch has been implemented to resolve this vulnerability by extending the buffer size to 6 bytes to properly accommodate SysEx UMP messages.

Description
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.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-120

Social media

Hype score
Not currently trending

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    @DarkNavyOrg

    23 May 2025

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    @VulmonFeeds

    19 May 2025

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  3. CVE-2025-37891 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… https://t.co/uKXS6NkasE

    @CVEnew

    19 May 2025

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Configurations

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References

Sources include official advisories and independent security research.