# CVE-2026-98150: bpf: Fix BPF_F_CPU validation for sparse CPU IDs

> A validation flaw in the Linux kernel BPF subsystem allows invalid CPU IDs to trigger a kernel crash, causing denial of service.

- **Severity:** High 7.0 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-98150, GHSA-m7rh-q276-2q3m, UBUNTU-CVE-2026-98150

## What is CVE-2026-98150?

CVE-2026-98150 is a high-severity vulnerability in Linux kernel, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

bpf: Fix BPF_F_CPU validation for sparse CPU IDs

BPF_F_CPU stores the target CPU ID in the upper 32 bits of the map
operation flags. bpf_map_check_op_flags() currently compares that ID
with num_possible_cpus(), which is the number of possible CPUs rather
than a bound on CPU IDs.

On an arm64 QEMU guest with a CPU device-tree hole, the possible CPU
mask was 0,2-3. A userspace program using raw bpf() syscalls creates
a BPF_MAP_TYPE_PERCPU_ARRAY and performs update and lookup operations
for each CPU by setting BPF_F_CPU and the CPU ID in the flags.

With the old check, CPU 1 is incorrectly accepted while valid CPU 3 is
rejected with -ERANGE. The CPU 1 update then reaches the per-CPU map
access path and triggers:

  Unable to handle kernel paging request at virtual address ...
  pc : __pi_memcpy_generic+0x5c/0x22c
  lr : bpf_percpu_array_update+0x2dc/0x2e8
  Call trace:
    __pi_memcpy_generic
    bpf_map_update_value
    map_update_elem
    __sys_bpf

Check the CPU ID against nr_cpu_ids and cpu_possible() instead. This
rejects CPU IDs outside the valid range and CPUs absent from the
possible mask, while allowing valid sparse CPU IDs.

## Which versions are affected by CVE-2026-98150?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-98150?

Apply the vendor's patch.

## Is CVE-2026-98150 being exploited?

There is no known exploitation of CVE-2026-98150 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98150 and fix it if it is affected.

What it is: CVE-2026-98150 is a high-severity vulnerability in Linux kernel, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-98150 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-98150/ (Markdown: https://insights.sbomify.com/CVE-2026-98150/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98150
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98150
- OSV: https://osv.dev/vulnerability/CVE-2026-98150

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98150/
Summaries are generated and may contain mistakes; the official description above is the record.
