Track vulnerabilities like this one. Sign up free to get alerted when software you use is affected.
6.3

CVE-2026-74278: Linux kernel ALSA bounce error can expose memory address

CVE-2026-74278 · published 2 months ago
Summary

The ALSA sound subsystem in certain Canonical Linux kernels can unintentionally reveal a kernel memory address to applications that receive a bounce error event. This leak could help an attacker learn details about the system’s inner workings. Install the latest kernel updates for the affected Ubuntu releases to apply the fix.

What to do
  • Update debian linux to version 6.12.100-1.
  • Update debian linux to version 7.1.5-1.
  • Update linux kernel to version 7.1.5.
  • Update canonical linux to version 6.8.0-147.147.
  • Update canonical linux-aws to version 6.8.0-1067.70.
  • Update canonical linux-aws-7.0 to version 7.0.0-1014.14~24.04.1.
  • Update canonical linux-azure to version 6.8.0-1071.79.
  • Update canonical linux-azure-7.0 to version 7.0.0-1017.17~24.04.1.
  • Update canonical linux-azure-fde to version 6.8.0-1069.76.
  • Update canonical linux-azure-fde-7.0 to version 7.0.0-1016.16~24.04.1.
  • Update canonical linux-gcp to version 6.8.0-1071.79.
  • Update canonical linux-gcp-7.0 to version 7.0.0-1014.14~24.04.1.
  • Update canonical linux-gke to version 6.8.0-1066.74.
  • Update canonical linux-gkeop to version 6.8.0-1052.56.
  • Update canonical linux-hwe-7.0 to version 7.0.0-38.38~24.04.4.
  • Update canonical linux-ibm to version 6.8.0-1067.68.
  • Update canonical linux-lowlatency to version 6.8.0-147.147.1.
  • Update canonical linux-oracle to version 6.8.0-1064.67.
  • Update canonical linux-oracle-7.0 to version 7.0.0-1013.13~24.04.1.
  • Update canonical linux-riscv-7.0 to version 7.0.0-38.38.1~24.04.1.
  • Update canonical linux-bluefield to version 6.8.0-1033.38.
  • Update canonical linux-realtime to version 6.8.1-1062.63.
  • Update canonical linux-aws-fips to version 6.8.0-1067.70+fips1.
  • Update canonical linux-azure-fips to version 6.8.0-1071.79+fips1.
  • Update canonical linux-fips to version 6.8.0-147.147+fips1.
  • Update canonical linux-gcp-fips to version 6.8.0-1071.79+fips1.
  • Update canonical linux to version 7.0.0-38.38.
  • Update canonical linux-aws to version 7.0.0-1014.14.
  • Update canonical linux-azure to version 7.0.0-1017.17.
  • Update canonical linux-azure-fde to version 7.0.0-1016.16.
  • Update canonical linux-gcp to version 7.0.0-1014.14.
  • Update canonical linux-gke to version 7.0.0-1008.9.
  • Update canonical linux-ibm to version 7.0.0-1015.15.
  • Update canonical linux-oem-7.0 to version 7.0.0-1015.15.
  • Update canonical linux-oracle to version 7.0.0-1013.13.
  • Update canonical linux-realtime to version 7.0.0-38.38.1.
  • Update canonical linux-riscv to version 7.0.0-38.38.1.
  • Update bellsoft linux-lts to version 6.1.191-r0.
  • Update bellsoft linux-lts to version 6.12.103-r0.
  • Update bellsoft linux-lts to version 6.18.43-r0.
Affected software
Ecosystem VendorProductAffected versions
Ubuntu:Pro:14.04:LTS canonical linux All versions
Ubuntu:Pro:14.04:LTS canonical linux-aws All versions
Ubuntu:Pro:14.04:LTS canonical linux-azure All versions
Ubuntu:Pro:14.04:LTS canonical linux-lts-xenial All versions
Ubuntu:Pro:16.04:LTS canonical linux-aws-hwe All versions
Ubuntu:Pro:16.04:LTS canonical linux-gcp All versions
Ubuntu:Pro:16.04:LTS canonical linux-hwe All versions
Ubuntu:16.04:LTS canonical linux-hwe-edge All versions
Ubuntu:Pro:16.04:LTS canonical linux-kvm All versions
Ubuntu:Pro:16.04:LTS canonical linux-oracle All versions
Ubuntu:Pro:FIPS:16.04:LTS canonical linux-fips All versions
Ubuntu:18.04:LTS canonical linux-aws-5.0 All versions
Ubuntu:18.04:LTS canonical linux-aws-5.3 All versions
Ubuntu:Pro:18.04:LTS canonical linux-aws-5.4 All versions
Ubuntu:Pro:18.04:LTS canonical linux-azure-4.15 All versions
Ubuntu:18.04:LTS canonical linux-azure-5.3 All versions
Ubuntu:Pro:18.04:LTS canonical linux-azure-5.4 All versions
Ubuntu:18.04:LTS canonical linux-azure-edge All versions
Ubuntu:Pro:18.04:LTS canonical linux-gcp-4.15 All versions
Ubuntu:18.04:LTS canonical linux-gcp-5.3 All versions
Ubuntu:Pro:18.04:LTS canonical linux-gcp-5.4 All versions
Ubuntu:18.04:LTS canonical linux-gke-4.15 All versions
Ubuntu:18.04:LTS canonical linux-gke-5.4 All versions
Ubuntu:18.04:LTS canonical linux-gkeop-5.4 All versions
Ubuntu:Pro:18.04:LTS canonical linux-hwe-5.4 All versions
Ubuntu:Pro:18.04:LTS canonical linux-ibm-5.4 All versions
Ubuntu:18.04:LTS canonical linux-oem All versions
Ubuntu:18.04:LTS canonical linux-oracle-5.0 All versions
Ubuntu:18.04:LTS canonical linux-oracle-5.3 All versions
Ubuntu:Pro:18.04:LTS canonical linux-oracle-5.4 All versions
Ubuntu:Pro:18.04:LTS canonical linux-raspi-5.4 All versions
Ubuntu:Pro:FIPS-updates:18.04:LTS canonical linux-aws-fips All versions
Ubuntu:Pro:FIPS-updates:18.04:LTS canonical linux-azure-fips All versions
Ubuntu:Pro:FIPS-updates:18.04:LTS canonical linux-gcp-fips All versions
Ubuntu:20.04:LTS canonical linux-aws-5.11 All versions
Ubuntu:20.04:LTS canonical linux-aws-5.13 All versions
Ubuntu:Pro:20.04:LTS canonical linux-aws-5.15 All versions
Ubuntu:20.04:LTS canonical linux-aws-5.8 All versions
Ubuntu:20.04:LTS canonical linux-azure-5.11 All versions
Ubuntu:20.04:LTS canonical linux-azure-5.13 All versions
Ubuntu:Pro:20.04:LTS canonical linux-azure-5.15 All versions
Ubuntu:20.04:LTS canonical linux-azure-5.8 All versions
Ubuntu:20.04:LTS canonical linux-azure-fde All versions
Ubuntu:Pro:20.04:LTS canonical linux-azure-fde-5.15 All versions
Ubuntu:Pro:20.04:LTS canonical linux-bluefield All versions
Ubuntu:20.04:LTS canonical linux-gcp-5.11 All versions
Ubuntu:20.04:LTS canonical linux-gcp-5.13 All versions
Ubuntu:Pro:20.04:LTS canonical linux-gcp-5.15 All versions
Ubuntu:20.04:LTS canonical linux-gcp-5.8 All versions
Ubuntu:20.04:LTS canonical linux-gke All versions
Showing 50 of 203. Show the rest
Ecosystem VendorProductAffected versions
Ubuntu:20.04:LTS canonical linux-gke-5.15 All versions
Ubuntu:20.04:LTS canonical linux-gkeop All versions
Ubuntu:20.04:LTS canonical linux-gkeop-5.15 All versions
Ubuntu:20.04:LTS canonical linux-hwe-5.11 All versions
Ubuntu:20.04:LTS canonical linux-hwe-5.13 All versions
Ubuntu:Pro:20.04:LTS canonical linux-hwe-5.15 All versions
Ubuntu:20.04:LTS canonical linux-hwe-5.8 All versions
Ubuntu:Pro:20.04:LTS canonical linux-ibm All versions
Ubuntu:Pro:20.04:LTS canonical linux-ibm-5.15 All versions
Ubuntu:20.04:LTS canonical linux-intel-5.13 All versions
Ubuntu:Pro:20.04:LTS canonical linux-intel-iotg-5.15 All versions
Ubuntu:Pro:20.04:LTS canonical linux-iot All versions
Ubuntu:Pro:20.04:LTS canonical linux-lowlatency-hwe-5.15 All versions
Ubuntu:Pro:20.04:LTS canonical linux-nvidia-tegra-5.15 All versions
Ubuntu:20.04:LTS canonical linux-oem-5.10 All versions
Ubuntu:20.04:LTS canonical linux-oem-5.13 All versions
Ubuntu:20.04:LTS canonical linux-oem-5.14 All versions
Ubuntu:20.04:LTS canonical linux-oem-5.6 All versions
Ubuntu:20.04:LTS canonical linux-oracle-5.11 All versions
Ubuntu:20.04:LTS canonical linux-oracle-5.13 All versions
Ubuntu:Pro:20.04:LTS canonical linux-oracle-5.15 All versions
Ubuntu:20.04:LTS canonical linux-oracle-5.8 All versions
Ubuntu:Pro:20.04:LTS canonical linux-raspi All versions
Ubuntu:20.04:LTS canonical linux-raspi2 All versions
Ubuntu:20.04:LTS canonical linux-riscv All versions
Ubuntu:20.04:LTS canonical linux-riscv-5.11 All versions
Ubuntu:Pro:20.04:LTS canonical linux-riscv-5.15 All versions
Ubuntu:20.04:LTS canonical linux-riscv-5.8 All versions
Ubuntu:Pro:20.04:LTS canonical linux-xilinx-zynqmp All versions
Ubuntu:22.04:LTS canonical linux-allwinner-5.19 All versions
Ubuntu:22.04:LTS canonical linux-aws-5.19 All versions
Ubuntu:22.04:LTS canonical linux-aws-6.2 All versions
Ubuntu:22.04:LTS canonical linux-aws-6.5 All versions
Ubuntu:22.04:LTS canonical linux-aws-6.8 All versions
Ubuntu:22.04:LTS canonical linux-azure-5.19 All versions
Ubuntu:22.04:LTS canonical linux-azure-6.2 All versions
Ubuntu:22.04:LTS canonical linux-azure-6.5 All versions
Ubuntu:22.04:LTS canonical linux-azure-6.8 All versions
Ubuntu:22.04:LTS canonical linux-azure-fde-5.19 All versions
Ubuntu:22.04:LTS canonical linux-azure-fde-6.2 All versions
Ubuntu:22.04:LTS canonical linux-azure-fde-6.8 All versions
Ubuntu:22.04:LTS canonical linux-gcp-5.19 All versions
Ubuntu:22.04:LTS canonical linux-gcp-6.2 All versions
Ubuntu:22.04:LTS canonical linux-gcp-6.5 All versions
Ubuntu:22.04:LTS canonical linux-gcp-6.8 All versions
Ubuntu:22.04:LTS canonical linux-hwe-5.19 All versions
Ubuntu:22.04:LTS canonical linux-hwe-6.2 All versions
Ubuntu:22.04:LTS canonical linux-hwe-6.5 All versions
Ubuntu:22.04:LTS canonical linux-hwe-6.8 All versions
Ubuntu:22.04:LTS canonical linux-ibm-6.8 All versions
Ubuntu:22.04:LTS canonical linux-intel-iot-realtime All versions
Ubuntu:22.04:LTS canonical linux-intel-iotg All versions
Ubuntu:22.04:LTS canonical linux-lowlatency All versions
Ubuntu:22.04:LTS canonical linux-lowlatency-hwe-5.19 All versions
Ubuntu:22.04:LTS canonical linux-lowlatency-hwe-6.2 All versions
Ubuntu:22.04:LTS canonical linux-lowlatency-hwe-6.5 All versions
Ubuntu:22.04:LTS canonical linux-lowlatency-hwe-6.8 All versions
Ubuntu:22.04:LTS canonical linux-nvidia All versions
Ubuntu:22.04:LTS canonical linux-nvidia-6.2 All versions
Ubuntu:22.04:LTS canonical linux-nvidia-6.5 All versions
Ubuntu:22.04:LTS canonical linux-nvidia-6.8 All versions
Ubuntu:22.04:LTS canonical linux-nvidia-tegra All versions
Ubuntu:22.04:LTS canonical linux-nvidia-tegra-igx All versions
Ubuntu:22.04:LTS canonical linux-oem-5.17 All versions
Ubuntu:22.04:LTS canonical linux-oem-6.0 All versions
Ubuntu:22.04:LTS canonical linux-oem-6.1 All versions
Ubuntu:22.04:LTS canonical linux-oem-6.5 All versions
Ubuntu:22.04:LTS canonical linux-oracle-6.5 All versions
Ubuntu:22.04:LTS canonical linux-oracle-6.8 All versions
Ubuntu:22.04:LTS canonical linux-realtime All versions
Ubuntu:22.04:LTS canonical linux-riscv-5.19 All versions
Ubuntu:22.04:LTS canonical linux-riscv-6.5 All versions
Ubuntu:22.04:LTS canonical linux-riscv-6.8 All versions
Ubuntu:22.04:LTS canonical linux-starfive-5.19 All versions
Ubuntu:22.04:LTS canonical linux-starfive-6.2 All versions
Ubuntu:22.04:LTS canonical linux-starfive-6.5 All versions
Ubuntu:Pro:Realtime:22.04:LTS canonical linux-realtime-6.8 All versions
Ubuntu:24.04:LTS canonical linux-aws-6.14 All versions
Ubuntu:24.04:LTS canonical linux-aws-6.17 All versions
Ubuntu:24.04:LTS canonical linux-aws-7.0 < 7.0.0-1014.14~24.04.1
Fix: upgrade to 7.0.0-1014.14~24.04.1
Ubuntu:24.04:LTS canonical linux-azure-6.11 All versions
Ubuntu:24.04:LTS canonical linux-azure-6.14 All versions
Ubuntu:24.04:LTS canonical linux-azure-6.17 All versions
Ubuntu:24.04:LTS canonical linux-azure-7.0 < 7.0.0-1017.17~24.04.1
Fix: upgrade to 7.0.0-1017.17~24.04.1
Ubuntu:24.04:LTS canonical linux-azure-fde-6.14 All versions
Ubuntu:24.04:LTS canonical linux-azure-fde-6.17 All versions
Ubuntu:24.04:LTS canonical linux-azure-fde-7.0 < 7.0.0-1016.16~24.04.1
Fix: upgrade to 7.0.0-1016.16~24.04.1
Ubuntu:24.04:LTS canonical linux-azure-nvidia All versions
Ubuntu:24.04:LTS canonical linux-azure-nvidia-6.14 All versions
Ubuntu:24.04:LTS canonical linux-gcp-6.11 All versions
Ubuntu:24.04:LTS canonical linux-gcp-6.14 All versions
Ubuntu:24.04:LTS canonical linux-gcp-6.17 All versions
Ubuntu:24.04:LTS canonical linux-gcp-7.0 < 7.0.0-1014.14~24.04.1
Fix: upgrade to 7.0.0-1014.14~24.04.1
Ubuntu:24.04:LTS canonical linux-hwe-6.11 All versions
Ubuntu:24.04:LTS canonical linux-hwe-6.14 All versions
Ubuntu:24.04:LTS canonical linux-hwe-6.17 All versions
Ubuntu:24.04:LTS canonical linux-hwe-7.0 < 7.0.0-38.38~24.04.4
Fix: upgrade to 7.0.0-38.38~24.04.4
Ubuntu:24.04:LTS canonical linux-lowlatency-hwe-6.11 All versions
Ubuntu:24.04:LTS canonical linux-nvidia-6.11 All versions
Ubuntu:24.04:LTS canonical linux-nvidia-6.17 All versions
Ubuntu:24.04:LTS canonical linux-nvidia-7.0 All versions
Ubuntu:24.04:LTS canonical linux-nvidia-lowlatency All versions
Ubuntu:24.04:LTS canonical linux-oem-6.11 All versions
Ubuntu:24.04:LTS canonical linux-oem-6.14 All versions
Ubuntu:24.04:LTS canonical linux-oem-6.17 All versions
Ubuntu:24.04:LTS canonical linux-oem-6.8 All versions
Ubuntu:24.04:LTS canonical linux-oracle-6.14 All versions
Ubuntu:24.04:LTS canonical linux-oracle-6.17 All versions
Ubuntu:24.04:LTS canonical linux-oracle-7.0 < 7.0.0-1013.13~24.04.1
Fix: upgrade to 7.0.0-1013.13~24.04.1
Ubuntu:24.04:LTS canonical linux-raspi-realtime All versions
Ubuntu:24.04:LTS canonical linux-riscv-6.14 All versions
Ubuntu:24.04:LTS canonical linux-riscv-6.17 All versions
Ubuntu:24.04:LTS canonical linux-riscv-7.0 < 7.0.0-38.38.1~24.04.1
Fix: upgrade to 7.0.0-38.38.1~24.04.1
Ubuntu:24.04:LTS canonical linux-xilinx All versions
Ubuntu:Pro:Realtime:24.04:LTS canonical linux-realtime-6.14 All versions
Ubuntu:Pro:Realtime:24.04:LTS canonical linux-realtime-6.17 All versions
Ubuntu:26.04:LTS canonical linux-nvidia-bos All versions
Ubuntu:26.04:LTS canonical linux-oem-7.0 < 7.0.0-1015.15
Fix: upgrade to 7.0.0-1015.15
– linux linux < 93d260ce43a81df579c98bee92b91316df9c1c57
2.6.12
< 05e2358fec8812c37516ccea63bc4b9956d864ba
Debian:11 debian linux All versions
Debian:12 debian linux All versions
Debian:13 debian linux < 6.12.100-1
Fix: upgrade to 6.12.100-1
Debian:14 debian linux < 7.1.5-1
Fix: upgrade to 7.1.5-1
Linux linux kernel >= 6.19.0, < 7.1.5
Fix: upgrade to 7.1.5
Ubuntu:24.04:LTS canonical linux < 6.8.0-147.147
Fix: upgrade to 6.8.0-147.147
Ubuntu:24.04:LTS canonical linux-aws < 6.8.0-1067.70
Fix: upgrade to 6.8.0-1067.70
Ubuntu:24.04:LTS canonical linux-azure < 6.8.0-1071.79
Fix: upgrade to 6.8.0-1071.79
Ubuntu:24.04:LTS canonical linux-azure-fde < 6.8.0-1069.76
Fix: upgrade to 6.8.0-1069.76
Ubuntu:24.04:LTS canonical linux-gcp < 6.8.0-1071.79
Fix: upgrade to 6.8.0-1071.79
Ubuntu:24.04:LTS canonical linux-gke < 6.8.0-1066.74
Fix: upgrade to 6.8.0-1066.74
Ubuntu:24.04:LTS canonical linux-gkeop < 6.8.0-1052.56
Fix: upgrade to 6.8.0-1052.56
Ubuntu:24.04:LTS canonical linux-ibm < 6.8.0-1067.68
Fix: upgrade to 6.8.0-1067.68
Ubuntu:24.04:LTS canonical linux-lowlatency < 6.8.0-147.147.1
Fix: upgrade to 6.8.0-147.147.1
Ubuntu:24.04:LTS canonical linux-oracle < 6.8.0-1064.67
Fix: upgrade to 6.8.0-1064.67
Ubuntu:Nvidia-BlueField:24.04:LTS canonical linux-bluefield < 6.8.0-1033.38
Fix: upgrade to 6.8.0-1033.38
Ubuntu:Pro:Realtime:24.04:LTS canonical linux-realtime < 6.8.1-1062.63
Fix: upgrade to 6.8.1-1062.63
Ubuntu:Pro:FIPS-updates:24.04:LTS canonical linux-aws-fips < 6.8.0-1067.70+fips1
Fix: upgrade to 6.8.0-1067.70+fips1
Ubuntu:Pro:FIPS-updates:24.04:LTS canonical linux-azure-fips < 6.8.0-1071.79+fips1
Fix: upgrade to 6.8.0-1071.79+fips1
Ubuntu:Pro:FIPS-updates:24.04:LTS canonical linux-fips < 6.8.0-147.147+fips1
Fix: upgrade to 6.8.0-147.147+fips1
Ubuntu:Pro:FIPS-updates:24.04:LTS canonical linux-gcp-fips < 6.8.0-1071.79+fips1
Fix: upgrade to 6.8.0-1071.79+fips1
Ubuntu:26.04:LTS canonical linux < 7.0.0-38.38
Fix: upgrade to 7.0.0-38.38
Ubuntu:26.04:LTS canonical linux-aws < 7.0.0-1014.14
Fix: upgrade to 7.0.0-1014.14
Ubuntu:26.04:LTS canonical linux-azure < 7.0.0-1017.17
Fix: upgrade to 7.0.0-1017.17
Ubuntu:26.04:LTS canonical linux-azure-fde < 7.0.0-1016.16
Fix: upgrade to 7.0.0-1016.16
Ubuntu:26.04:LTS canonical linux-gcp < 7.0.0-1014.14
Fix: upgrade to 7.0.0-1014.14
Ubuntu:26.04:LTS canonical linux-gke < 7.0.0-1008.9
Fix: upgrade to 7.0.0-1008.9
Ubuntu:26.04:LTS canonical linux-ibm < 7.0.0-1015.15
Fix: upgrade to 7.0.0-1015.15
Ubuntu:26.04:LTS canonical linux-oracle < 7.0.0-1013.13
Fix: upgrade to 7.0.0-1013.13
Ubuntu:26.04:LTS canonical linux-realtime < 7.0.0-38.38.1
Fix: upgrade to 7.0.0-38.38.1
Ubuntu:26.04:LTS canonical linux-riscv < 7.0.0-38.38.1
Fix: upgrade to 7.0.0-38.38.1
Alpaquita:23 bellsoft linux-lts >= 6.1.189-r0, < 6.1.191-r0
Fix: upgrade to 6.1.191-r0
Alpaquita:25 bellsoft linux-lts >= 6.12.95-r0, < 6.12.103-r0
Fix: upgrade to 6.12.103-r0
Alpaquita:stream bellsoft linux-lts >= 6.18.38-r0, < 6.18.43-r0
Fix: upgrade to 6.18.43-r0
Original advisory text
BELL-CVE-2026-74278
In the Linux kernel, the following vulnerability has been resolved:

ALSA: seq: Fix kernel heap address leak in bounce_error_event()

The comment above bounce_error_event() documents that user clients
should receive SNDRV_SEQ_EVENT_BOUNCE with the original event embedded
as variable-length data, while kernel clients should receive
SNDRV_SEQ_EVENT_KERNEL_ERROR with a quoted kernel pointer.

However, the implementation unconditionally uses
SNDRV_SEQ_EVENT_KERNEL_ERROR with data.quote.event set to the raw
struct snd_seq_event pointer for all clients. When a bounce error
event is delivered to a USER_CLIENT via snd_seq_read(), the kernel
heap address in data.quote.event is exposed to userspace through
copy_to_user() in the fixed-length branch.

This is a distinct leak path from the one addressed by commit
705dd6dcbc0e ("ALSA: seq: Clear variable event pointer on read"),
which sanitizes data.ext.ptr in the variable-length branch of
snd_seq_read(). The bounce_error_event() leak uses fixed-length
events that take the else branch where no sanitization occurs.

Differentiate the bounce event by client type. For USER_CLIENT,
send SNDRV_SEQ_EVENT_BOUNCE with SNDRV_SEQ_EVENT_LENGTH_VARIABLE
and data.ext pointing to the original event. The variable-length
path in snd_seq_event_dup() copies the event data into chained
cells, and snd_seq_expand_var_event() copies only the content --
never the pointer -- to userspace. For KERNEL_CLIENT, keep the
existing SNDRV_SEQ_EVENT_KERNEL_ERROR behavior with the quoted
pointer.
References
Severity
6.3 Medium
Exploitation
<1% chance of attack within 30 days
Timeline
Published18 Aug 2026
Updated4 Nov 2026
First seen15 Aug 2026
Track software like this
Free during beta