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high 7.8

CVE-2025-37891 json

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

published last yr. modified 25d ago also EUVD-2025-15684

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits
0
none known

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.

Patch / fix

  • Linux Linux 6.6.90, 6.12.28, 6.14.6, 6.15
  • linux Debian 14, Debian 13 6.12.29-1

debian advisories DEBIAN-CVE-2025-37891

  • linux Ubuntu 24.04 LTS 6.8.0-100.100
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1046.49
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1047.50
  • linux-gke Ubuntu 24.04 LTS 6.8.0-1043.48
  • linux-ibm Ubuntu 24.04 LTS 6.8.0-1044.44
  • linux-azure Ubuntu 24.04 LTS 6.8.0-1046.52
  • linux-gkeop Ubuntu 24.04 LTS 6.8.0-1030.33
  • linux-raspi Ubuntu 24.04 LTS 6.8.0-1047.51

ubuntu advisories UBUNTU-CVE-2025-37891

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel enterprise linux eus 10.0 6.12.0-55.55.1.el10_0
  • rv enterprise linux eus 10.0 6.12.0-55.55.1.el10_0
  • perf enterprise linux eus 10.0 6.12.0-55.55.1.el10_0
  • rtla enterprise linux eus 10.0 6.12.0-55.55.1.el10_0
  • libperf enterprise linux eus 10.0 6.12.0-55.55.1.el10_0
  • kernel-rt enterprise linux eus 10.0 6.12.0-55.55.1.el10_0
  • kernel-64k enterprise linux eus 10.0 6.12.0-55.55.1.el10_0
  • kernel-core enterprise linux eus 10.0 6.12.0-55.55.1.el10_0

red hat advisories RHSA-2026:1236RHSA-2026:0917RHSA-2026:0804

  • kernel-coco SLE Module for Confidential Computing Technical Preview 15 SP6 6.4.0-15061.28.coco15sp6.1
  • kernel-syms-coco SLE Module for Confidential Computing Technical Preview 15 SP6 6.4.0-15061.28.coco15sp6.1
  • kernel-coco_debug SLE Module for Confidential Computing Technical Preview 15 SP6 6.4.0-15061.28.coco15sp6.1
  • kernel-source-coco SLE Module for Confidential Computing Technical Preview 15 SP6 6.4.0-15061.28.coco15sp6.1
  • kernel-rt Real Time Module 15 SP7 6.4.0-150700.7.8.1
  • kernel-syms-rt Real Time Module 15 SP7 6.4.0-150700.7.8.1
  • kernel-source-rt Real Time Module 15 SP7 6.4.0-150700.7.8.1
  • kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.6.1

suse advisories SUSE-SU-2025:02923-1SUSE-SU-2025:02333-1SUSE-SU-2025:02307-1SUSE-SU-2025:02254-1SUSE-SU-2025:02000-1SUSE-SU-2025:20413-1

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2025-37891 updated cvss 7.1

kernel: Linux kernel: ALSA: ump buffer overflow via malformed UMP SysEx message

  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +82 more Red Hat Enterprise Linux 10 kernel
    affected: workaround, no fix available
  • Red Hat CodeReady Linux Builder EUS (v.9.4) libperf 5.14.0-427.107.1.el9_4, kernel-debuginfo-common-s390x 5.14.0-427.107.1.el9_4, kernel-debuginfo-common-x86_64 5.14.0-427.107.1.el9_4, kernel-debuginfo-common-aarch64 5.14.0-427.107.1.el9_4, kernel-debuginfo-common-ppc64le 5.14.0-427.107.1.el9_4
    fixed: vendor fix RHSA-2026:0917
  • Red Hat CodeReady Linux Builder EUS (v.9.6) libperf 5.14.0-570.79.1.el9_6, kernel-debuginfo-common-s390x 5.14.0-570.79.1.el9_6, kernel-debuginfo-common-x86_64 5.14.0-570.79.1.el9_6, kernel-debuginfo-common-aarch64 5.14.0-570.79.1.el9_6, kernel-debuginfo-common-ppc64le 5.14.0-570.79.1.el9_6
    fixed: vendor fix RHSA-2026:0804
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0) rv 6.12.0-55.55.1.el10_0, perf 6.12.0-55.55.1.el10_0, rtla 6.12.0-55.55.1.el10_0, python3-perf 6.12.0-55.55.1.el10_0, kernel-devel-matched 6.12.0-55.55.1.el10_0, kernel-64k-devel-matched 6.12.0-55.55.1.el10_0, +7 more
    fixed: vendor fix RHSA-2026:1236
  • Red Hat Enterprise Linux AppStream EUS (v.9.4) rv 5.14.0-427.107.1.el9_4, perf 5.14.0-427.107.1.el9_4, rtla 5.14.0-427.107.1.el9_4, kernel-devel-matched 5.14.0-427.107.1.el9_4, kernel-64k-devel-matched 5.14.0-427.107.1.el9_4, kernel-debug-devel-matched 5.14.0-427.107.1.el9_4, +6 more
    fixed: vendor fix RHSA-2026:0917
  • Red Hat Enterprise Linux AppStream EUS (v.9.6) rv 5.14.0-570.79.1.el9_6, perf 5.14.0-570.79.1.el9_6, rtla 5.14.0-570.79.1.el9_6, python3-perf 5.14.0-570.79.1.el9_6, kernel-devel-matched 5.14.0-570.79.1.el9_6, kernel-64k-devel-matched 5.14.0-570.79.1.el9_6, +7 more
    fixed: vendor fix RHSA-2026:0804
  • Red Hat Enterprise Linux BaseOS EUS (v. 10.0) kernel 6.12.0-55.55.1.el10_0, kernel-64k 6.12.0-55.55.1.el10_0, kernel-core 6.12.0-55.55.1.el10_0, kernel-tools 6.12.0-55.55.1.el10_0, kernel-modules 6.12.0-55.55.1.el10_0, kernel-64k-core 6.12.0-55.55.1.el10_0, +27 more
    fixed: vendor fix RHSA-2026:1236
  • Red Hat Enterprise Linux BaseOS EUS (v.9.4) bpftool 7.3.0-427.107.1.el9_4, kernel 5.14.0-427.107.1.el9_4, kernel-64k 5.14.0-427.107.1.el9_4, kernel-core 5.14.0-427.107.1.el9_4, kernel-tools 5.14.0-427.107.1.el9_4, python3-perf 5.14.0-427.107.1.el9_4, +28 more
    fixed: vendor fix RHSA-2026:0917
show 8 more
  • Red Hat Enterprise Linux BaseOS EUS (v.9.6) kernel 5.14.0-570.79.1.el9_6, kernel-64k 5.14.0-570.79.1.el9_6, kernel-core 5.14.0-570.79.1.el9_6, kernel-tools 5.14.0-570.79.1.el9_6, kernel-modules 5.14.0-570.79.1.el9_6, kernel-64k-core 5.14.0-570.79.1.el9_6, +27 more
    fixed: vendor fix RHSA-2026:0804
  • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) libperf 6.12.0-55.55.1.el10_0, kernel-debuginfo-common-s390x 6.12.0-55.55.1.el10_0, kernel-debuginfo-common-x86_64 6.12.0-55.55.1.el10_0, kernel-debuginfo-common-aarch64 6.12.0-55.55.1.el10_0, kernel-debuginfo-common-ppc64le 6.12.0-55.55.1.el10_0 Red Hat Enterprise Linux Real Time EUS (v. 10.0) kernel-rt 6.12.0-55.55.1.el10_0, kernel-rt-64k 6.12.0-55.55.1.el10_0, kernel-rt-core 6.12.0-55.55.1.el10_0, kernel-rt-modules 6.12.0-55.55.1.el10_0, kernel-rt-64k-core 6.12.0-55.55.1.el10_0, kernel-rt-debug-core 6.12.0-55.55.1.el10_0, +14 more
    fixed: vendor fix RHSA-2026:1236
  • Red Hat Enterprise Linux Real Time EUS (v.9.4) kernel-rt 5.14.0-427.107.1.el9_4, kernel-rt-core 5.14.0-427.107.1.el9_4, kernel-rt-modules 5.14.0-427.107.1.el9_4, kernel-rt-debug-core 5.14.0-427.107.1.el9_4, kernel-rt-modules-core 5.14.0-427.107.1.el9_4, kernel-rt-debug-modules 5.14.0-427.107.1.el9_4, +4 more
    fixed: vendor fix RHSA-2026:0917
  • Red Hat Enterprise Linux Real Time EUS (v.9.6) kernel-rt 5.14.0-570.79.1.el9_6, kernel-rt-64k 5.14.0-570.79.1.el9_6, kernel-rt-core 5.14.0-570.79.1.el9_6, kernel-rt-modules 5.14.0-570.79.1.el9_6, kernel-rt-64k-core 5.14.0-570.79.1.el9_6, kernel-rt-debug-core 5.14.0-570.79.1.el9_6, +14 more
    fixed: vendor fix RHSA-2026:0804
  • Red Hat Enterprise Linux Real Time for NFV EUS (v. 10.0) kernel-rt 6.12.0-55.55.1.el10_0, kernel-rt-kvm 6.12.0-55.55.1.el10_0, kernel-rt-core 6.12.0-55.55.1.el10_0, kernel-rt-modules 6.12.0-55.55.1.el10_0, kernel-rt-debug-kvm 6.12.0-55.55.1.el10_0, kernel-rt-debug-core 6.12.0-55.55.1.el10_0, +6 more
    fixed: vendor fix RHSA-2026:1236
  • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.4) kernel-rt 5.14.0-427.107.1.el9_4, kernel-rt-kvm 5.14.0-427.107.1.el9_4, kernel-rt-core 5.14.0-427.107.1.el9_4, kernel-rt-modules 5.14.0-427.107.1.el9_4, kernel-rt-debug-kvm 5.14.0-427.107.1.el9_4, kernel-rt-debug-core 5.14.0-427.107.1.el9_4, +6 more
    fixed: vendor fix RHSA-2026:0917
  • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.6) kernel-rt 5.14.0-570.79.1.el9_6, kernel-rt-kvm 5.14.0-570.79.1.el9_6, kernel-rt-core 5.14.0-570.79.1.el9_6, kernel-rt-modules 5.14.0-570.79.1.el9_6, kernel-rt-debug-kvm 5.14.0-570.79.1.el9_6, kernel-rt-debug-core 5.14.0-570.79.1.el9_6, +6 more
    fixed: vendor fix RHSA-2026:0804
  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-selftests-internal
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
25d ago

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Linux Linux

Classification

Weakness
  • CWE-120 Buffer Copy without Checking Size of Input
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.