Description
In the Linux kernel, the following vulnerability has been resolved:
perf: arm_pmuv3: Zero initialize hw_id branch stack field
PERF_SAMPLE_BRANCH_HW_INDEX is supported by BRBE so hw_id is passed to
userspace, but it's never set by the BRBE driver. Zero initialize it as
it should be according to the docs:
* For the architectures whose raw branch records are
* already stored in age order, the hw_idx should be 0.
It's probably too risky to remove PERF_SAMPLE_BRANCH_HW_INDEX from BRBE
now in case anyone is setting it and reading the value, but zero
initializing the whole struct also protects against the same issue with
new fields that are added in the future.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.17 | 6.18.52 |
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 | 7.2.6-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | linux | 7.0.0-42.42 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-aws | 7.0.0-1016.17 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-azure | 7.0.0-1020.21 | USN-9019-1 |
| Ubuntu 26.04 LTS | linux-azure-fde | 7.0.0-1019.19 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-gcp | 7.0.0-1016.18 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-gke | 7.0.0-1010.11 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-ibm +1 | 7.0.0-1017.17 | USN-8960-1, USN-8959-1 |
| Ubuntu 26.04 LTS | linux-nvidia +1 | No fix yet | — |
| Ubuntu 26.04 LTS | linux-oracle | 7.0.0-1015.16 | USN-8959-1 |
| Ubuntu 26.04 LTS | linux-raspi | 7.0.0-1023.23 | USN-9021-1 |
| Ubuntu 26.04 LTS | linux-realtime | 7.0.0-43.43.1 | USN-9020-1 |
| Ubuntu 26.04 LTS | linux-riscv | 7.0.0-42.42.1 | — |
| Ubuntu 24.04 LTS | linux-aws-7.0 | 7.0.0-1017.18~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-azure-fde-7.0 | 7.0.0-1019.19~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-gcp-7.0 | 7.0.0-1017.19~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-hwe-7.0 | 7.0.0-42.42~24.04.1 | USN-8959-1 |
| Ubuntu 24.04 LTS | linux-oracle-7.0 | 7.0.0-1016.18~24.04.1 | USN-9020-1 |
| Ubuntu 24.04 LTS | linux-riscv +29 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv-7.0 | 7.0.0-42.42.1~24.04.1 | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
Show 2 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 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | kernel-source | 7.2.7-1.1 | openSUSE-SU-2026:11880-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | kernel-livepatch-6.18.54-121.166 | 1:1.0-0.amzn2023 | ALAS2023-2026-3192 |
| Amazon Linux 2023 | perf6.18 +12 | 1:6.18.54-121.166.amzn2023 | ALAS2023-2026-3192 |
Advisories 8
- USN-9020-1 linux-aws-7.0, linux-azure-fde, linux-azure-fde-7.0, linux-gcp-7.0, linux-gke, linux-oracle-7.0, linux-realtime vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8959-1 linux, linux-aws, linux-gcp, linux-hwe-7.0, linux-ibm, linux-oracle vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-9021-1 linux-raspi vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-9019-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- USN-8960-1 linux-oem-7.0 vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- WID-SEC-2026-3444 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- ALAS2023-2026-3192 Important: kernel6.18 security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Oct 26, 2026
- openSUSE-SU-2026:11880-1 kernel-devel-7.2.7-1.1 on GA media SUSE / openSUSE Security Updates · Sep 25, 2026