Description
In the Linux kernel, the following vulnerability has been resolved:
hwrng: virtio - Fix race on data_avail and actual data
The virtio rng device kicks off a new entropy request whenever the
data available reaches zero. When a new request occurs at the end
of a read operation, that is, when the result of that request is
only needed by the next reader, then there is a race between the
writing of the new data and the next reader.
This is because there is no synchronisation whatsoever between the
writer and the reader.
Fix this by writing data_avail with smp_store_release and reading
it with smp_load_acquire when we first enter read. The subsequent
reads are safe because they're either protected by the first load
acquire, or by the completion mechanism.
Also remove the redundant zeroing of data_idx in random_recv_done
(data_idx must already be zero at this point) and data_avail in
request_entropy (ditto).
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 2.6.26 | 4.19.291 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 6.4.4-1 | — |
| Debian 13 | linux | 6.4.4-1 | — |
| Debian 12 | linux | 6.1.52-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Nvidia-BlueField 22.04 LTS | linux-bluefield | 5.15.0-1027.29 | — |
| Ubuntu 24.04 LTS | linux-riscv +10 | No fix yet | — |
| Ubuntu 22.04 LTS | linux | 5.15.0-86.96 | — |
| Ubuntu 22.04 LTS | linux-aws | 5.15.0-1047.52 | — |
| Ubuntu 22.04 LTS | linux-azure | 5.15.0-1049.56 | — |
| Ubuntu 22.04 LTS | linux-azure-fde | 5.15.0-1049.56.1 | — |
| Ubuntu 22.04 LTS | linux-gcp | 5.15.0-1044.52 | — |
| Ubuntu 22.04 LTS | linux-gke +1 | 5.15.0-1044.49 | — |
| Ubuntu 22.04 LTS | linux-gkeop | 5.15.0-1030.35 | — |
| Ubuntu 22.04 LTS | linux-ibm +1 | 5.15.0-1040.43 | — |
| Ubuntu 22.04 LTS | linux-intel-iotg | 5.15.0-1043.49 | — |
| Ubuntu 22.04 LTS | linux-lowlatency | 5.15.0-86.95 | — |
| Ubuntu 22.04 LTS | linux-nvidia | 5.15.0-1037.37 | — |
| Ubuntu 22.04 LTS | linux-nvidia-tegra | 5.15.0-1018.18 | — |
| Ubuntu 22.04 LTS | linux-nvidia-tegra-igx | 5.15.0-1005.5 | — |
| Ubuntu 22.04 LTS | linux-oracle | 5.15.0-1045.51 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-xilinx-zynqmp | 5.15.0-1025.29 | — |
| Ubuntu 20.04 LTS | linux | 5.4.0-166.183 | — |
| Ubuntu 20.04 LTS | linux-aws | 5.4.0-1113.123 | — |
| Ubuntu 20.04 LTS | linux-aws-5.15 | 5.15.0-1047.52~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-azure | 5.4.0-1119.126 | — |
| Ubuntu 20.04 LTS | linux-azure-5.15 | 5.15.0-1049.56~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-bluefield | 5.4.0-1074.80 | — |
| Ubuntu 20.04 LTS | linux-gcp | 5.4.0-1117.126 | — |
| Ubuntu 20.04 LTS | linux-gcp-5.15 | 5.15.0-1044.52~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-hwe-5.15 | 5.15.0-86.96~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-ibm | 5.4.0-1060.65 | — |
| Ubuntu 20.04 LTS | linux-ibm-5.15 | 5.15.0-1040.43~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-intel-iotg-5.15 | 5.15.0-1043.49~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-iot | 5.4.0-1025.26 | — |
| Ubuntu 20.04 LTS | linux-kvm | 5.4.0-1102.108 | — |
| Ubuntu 20.04 LTS | linux-lowlatency-hwe-5.15 | 5.15.0-86.95~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-nvidia-tegra-5.15 | 5.15.0-1018.18~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-oracle | 5.4.0-1112.121 | — |
| Ubuntu 20.04 LTS | linux-oracle-5.15 | 5.15.0-1045.51~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-raspi | 5.4.0-1097.109 | — |
| Ubuntu 20.04 LTS | linux-riscv-5.15 | 5.15.0-1043.47~20.04.1 | — |
| Ubuntu 20.04 LTS | linux-xilinx-zynqmp | 5.4.0-1033.37 | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 12 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-intel-iot-realtime | 5.15.0-1040.42 | — |
| Ubuntu Pro Realtime 22.04 LTS | linux-realtime | 5.15.0-1048.54 | — |
| Ubuntu Pro FIPS 20.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS 18.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS 16.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-aws-fips | 5.4.0-1113.123+fips1 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-azure-fips | 5.4.0-1119.126+fips1 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-fips | 5.4.0-1088.97 | — |
| Ubuntu Pro FIPS-updates 20.04 LTS | linux-gcp-fips | 5.4.0-1117.126+fips1 | — |
| Ubuntu Pro FIPS-updates 18.04 LTS | linux-fips +3 | No fix yet | — |
| Ubuntu Pro FIPS-updates 16.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro FIPS-preview 22.04 LTS | linux-fips | No fix yet | — |
| Ubuntu Pro 18.04 LTS | linux +5 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | linux-aws-5.4 | 5.4.0-1113.123~18.04.1 | — |
| Ubuntu Pro 18.04 LTS | linux-azure-5.4 | 5.4.0-1119.126~18.04.2 | — |
| Ubuntu Pro 18.04 LTS | linux-gcp-5.4 | 5.4.0-1117.126~18.04.1 | — |
| Ubuntu Pro 18.04 LTS | linux-hwe-5.4 | 5.4.0-166.183~18.04.2 | — |
| Ubuntu Pro 18.04 LTS | linux-ibm-5.4 | 5.4.0-1060.65~18.04.1 | — |
| Ubuntu Pro 18.04 LTS | linux-oracle-5.4 | 5.4.0-1112.121~18.04.4 | — |
| Ubuntu Pro 18.04 LTS | linux-raspi-5.4 | 5.4.0-1097.109~18.04.2 | — |
| Ubuntu Pro 16.04 LTS | linux +7 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | linux +3 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | kernel-64kb +6 | 6.4.0-150700.53.28.1 | SUSE-SU-2026:0315-1 |
| SLES 15 SP7 | kernel-azure +2 | 6.4.0-150700.20.24.1 | SUSE-SU-2026:0281-1 |
| SLES 15 SP7 | kernel-default-base | 6.4.0-150700.53.28.1.150700.17.19.1 | SUSE-SU-2026:0315-1 |
| SLES 15 SP6 | kernel-64kb +6 | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| SLES 15 SP6 | kernel-default-base | 6.4.0-150600.23.84.1.150600.12.38.1 | SUSE-SU-2026:0293-1 |
| SLES 15 SP5 | kernel-64kb +6 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLES 15 SP5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLES 15 SP4 | kernel-64kb +6 | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLES 15 SP4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
Show 15 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | kernel-default-base | 6.4.0-150600.23.84.1.150600.12.38.1 | SUSE-SU-2026:0293-1 |
| SLES for SAP 15 SP6 | kernel-docs +4 | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| SLES for SAP 15 SP5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLES for SAP 15 SP5 | kernel-docs +4 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLES for SAP 15 SP4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SLES for SAP 15 SP4 | kernel-docs +4 | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE Micro 6.1 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.1 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20876-1 |
| SLE Micro 6.1 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20498-1 |
| SLE Micro 6.0 | kernel-default-base | 6.4.0-39.1.21.16 | SUSE-SU-2026:20477-1 |
| SLE Micro 6.0 | kernel-rt +1 | 6.4.0-40.1 | SUSE-SU-2026:20845-1 |
| SLE Micro 6.0 | kernel-source +2 | 6.4.0-39.1 | SUSE-SU-2026:20477-1 |
| SLE Micro 5.5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLE Micro 5.5 | kernel-rt +1 | 5.14.21-150500.13.118.1 | SUSE-SU-2026:0263-1 |
| SLE Micro 5.5 | kernel-source +1 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLE Micro 5.4 | kernel-default | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.4 | kernel-rt +1 | 5.14.21-150400.15.142.1 | SUSE-SU-2026:0411-1 |
| SLE Micro 5.3 | kernel-default | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.3 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SLE Micro 5.3 | kernel-rt +1 | 5.14.21-150400.15.142.1 | SUSE-SU-2026:0411-1 |
| SLE Live Patching 15 SP7 | kernel-default | 6.4.0-150700.53.28.1 | SUSE-SU-2026:0315-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7-RT_Update_8 | 1-150700.1.3.1 | SUSE-SU-2026:0278-1 |
| SLE Live Patching 15 SP7 | kernel-livepatch-SLE15-SP7_Update_8 | 1-150700.15.3.1 | SUSE-SU-2026:0315-1 |
| SLE Live Patching 15 SP6 | kernel-default | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| SLE Live Patching 15 SP6 | kernel-livepatch-SLE15-SP6_Update_19 | 1-150600.13.3.1 | SUSE-SU-2026:0293-1 |
| SLE Live Patching 15 SP5 | kernel-default | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLE Live Patching 15 SP5 | kernel-livepatch-SLE15-SP5_Update_34 | 1-150500.11.3.1 | SUSE-SU-2026:0317-1 |
| SLE Live Patching 15 SP4 | kernel-default | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE Live Patching 15 SP4 | kernel-livepatch-SLE15-SP4_Update_48 | 1-150400.9.7.1 | SUSE-SU-2026:0617-1 |
| SLE HPC 15 SP5 | kernel-64kb +5 | 5.14.21-150500.55.133.1 | SUSE-SU-2026:0317-1 |
| SLE HPC 15 SP5 | kernel-default-base | 5.14.21-150500.55.133.1.150500.6.65.1 | SUSE-SU-2026:0317-1 |
| SLE HPC 15 SP4 | kernel-64kb +5 | 5.14.21-150400.24.194.1 | SUSE-SU-2026:0617-1 |
| SLE HPC 15 SP4 | kernel-default-base | 5.14.21-150400.24.194.1.150400.24.98.3 | SUSE-SU-2026:0617-1 |
| SUSE Real Time Module 15 SP7 | kernel-rt +2 | 6.4.0-150700.7.28.1 | SUSE-SU-2026:0278-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.6 | dtb-aarch64 +10 | 6.4.0-150600.23.84.1 | SUSE-SU-2026:0293-1 |
| openSUSE Leap 15.6 | kernel-default-base | 6.4.0-150600.23.84.1.150600.12.38.1 | SUSE-SU-2026:0293-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.1.41-63.109 | 1.0-0.amzn2023 | ALAS2023-2023-299 |
| Amazon Linux 2023 | perf +12 | 6.1.41-63.109.amzn2023 | ALAS2023-2023-299 |
| Amazon Linux 2 | kernel-livepatch-4.14.344-262.563 | 1.0-0.amzn2 | ALAS2-2024-2588 |
| Amazon Linux 2 | perf +8 | 4.14.344-262.563.amzn2 | ALAS2-2024-2588 |
Advisories 15
- WID-SEC-2025-2920 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- SUSE-SU-2026:20876-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 31, 2026
- SUSE-SU-2026:20845-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 28, 2026
- SUSE-SU-2026:20498-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:20477-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0293-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0317-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0281-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0278-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0315-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2026:0617-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 26, 2026
- ALAS2023-2023-299 Important: kernel security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Feb 11, 2026
- SUSE-SU-2026:0411-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 10, 2026
- ALAS2-2024-2588 Important: kernel security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Feb 8, 2026
- SUSE-SU-2026:0263-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
References
- https://git.kernel.org/stable/c/241ef15776a7c8505008db689175b320d345ecd3
- https://git.kernel.org/stable/c/a43bcb0b661cbbf3ad797d2aee6b6fd06b8fc69d
- https://git.kernel.org/stable/c/77471e4912d3960dafe141e268c44be8024fe4dc
- https://git.kernel.org/stable/c/c76d991b6f01a5d931e7053a73bc9524975a5215
- https://git.kernel.org/stable/c/22c30022cde6e2c88612b3a499223cfa912f1bc7
- https://git.kernel.org/stable/c/318657b4c2077289659f1cd9e2a34f6a3b208e3e
- https://git.kernel.org/stable/c/2fc91f156b3f3446a1bce80cf4adedcbf41271c2
- https://git.kernel.org/stable/c/ac52578d6e8d300dd50f790f29a24169b1edd26c