# CVE-2026-64280: fpga: dfl-afu: validate DMA mapping length in afu_dma_map_region()

> A missing upper bound check in the Linux kernel FPGA driver allows integer truncation, potentially leading to denial of service or privilege escalation.

- **Severity:** High 8.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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 Jul 2026
- **Updated:** 23 Aug 2026
- **Also known as:** BELL-CVE-2026-64280, DEBIAN-CVE-2026-64280, GHSA-hj85-3f53-vrg4, ROOT-OS-DEBIAN-12-CVE-2026-64280, ROOT-OS-DEBIAN-13-CVE-2026-64280, ROOT-OS-UBUNTU-2204-CVE-2026-64280, UBUNTU-CVE-2026-64280

## What is CVE-2026-64280?

CVE-2026-64280 is a high-severity vulnerability in Linux kernel, published on 25 Jul 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:

fpga: dfl-afu: validate DMA mapping length in afu_dma_map_region()

afu_ioctl_dma_map() accepts a 64-bit length from userspace via
DFL_FPGA_PORT_DMA_MAP ioctl without an upper bound check. The value
is passed to afu_dma_pin_pages() where npages is derived as
length >> PAGE_SHIFT and passed to pin_user_pages_fast() which takes
int nr_pages, causing implicit truncation if length is very large.

Validate map.length at the ioctl entry point before calling
afu_dma_map_region(), rejecting values whose page count exceeds
INT_MAX.

## Which versions are affected by CVE-2026-64280?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64280?

Apply the vendor's patch.

## Is CVE-2026-64280 being exploited?

There is no known exploitation of CVE-2026-64280 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-2026-64280 and fix it if it is affected.

What it is: CVE-2026-64280 is a high-severity vulnerability in Linux kernel, published on 25 Jul 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-2026-64280 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-2026-64280/ (Markdown: https://insights.sbomify.com/CVE-2026-64280/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64280
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64280
- OSV: https://osv.dev/vulnerability/CVE-2026-64280

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64280/
Summaries are generated and may contain mistakes; the official description above is the record.