Description
In the Linux kernel, the following vulnerability has been resolved:
ring-buffer: Do not show buffer_meta for CPUs without a buffer
The per_cpu/cpuN/buffer_meta files are created for every possible CPU,
but buffer->buffers[cpu] is only allocated once that CPU comes online.
Reading the file of a CPU that never came online dereferences a NULL
cpu_buffer in rbm_start().
Fail the open with -ENODEV when the CPU has no buffer, as the other
per CPU ring buffer interfaces do.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.12 | 6.12.115 |
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 | 7.2.13-1 | — |
| Debian 13 | linux | 6.12.115-2 | — |
| Debian 12 | linux-6.12 | 6.12.115-2~deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | linux | 7.3.0-10.10 | — |
| Ubuntu 26.10 | linux-aws +4 | 7.3.0-1004.4 | — |
| Ubuntu 26.10 | linux-azure-fde | 7.3.0-1004.5 | — |
| Ubuntu 26.10 | linux-riscv +1 | 7.3.0-10.10.1 | — |
| Ubuntu 26.04 LTS | linux +14 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv +35 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.12.115-140.210 | 1:1.0-0.amzn2023 | ALAS2023-2026-3448 |
| Amazon Linux 2023 | perf6.12 +11 | 1:6.12.115-140.210.amzn2023 | ALAS2023-2026-3448 |
Advisories 2
- WID-SEC-2026-4224 Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff BSI CERT-Bund (WID) · Nov 12, 2026
- ALAS2023-2026-3448 Important: kernel6.12 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Nov 12, 2026