# CVE-2026-53172: accel/ethosu: fix IFM region index out-of-bounds in command stream parser

> A local attacker can trigger an out-of-bounds write in the Ethos-U NPU driver, potentially leading to kernel memory corruption and privilege escalation.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/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 Jun 2026
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-53172, GHSA-jf8x-7724-7vrr, UBUNTU-CVE-2026-53172

## What is CVE-2026-53172?

CVE-2026-53172 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Jun 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:

accel/ethosu: fix IFM region index out-of-bounds in command stream parser

NPU_SET_IFM_REGION extracts the region index with param & 0x7f, giving
a maximum value of 127. However region_size[] and output_region[] in
struct ethosu_validated_cmdstream_info are both sized to
NPU_BASEP_REGION_MAX (8), giving valid indices [0..7].

Every other region assignment in the same switch uses param & 0x7:
  NPU_SET_OFM_REGION:  st.ofm.region  = param & 0x7;
  NPU_SET_IFM2_REGION: st.ifm2.region = param & 0x7;
  NPU_SET_WEIGHT_REGION: st.weight[0].region = param & 0x7;
  NPU_SET_SCALE_REGION:  st.scale[0].region  = param & 0x7;

The 0x7f mask on IFM is inconsistent and appears to be a typo.

feat_matrix_length() and calc_sizes() use the region index directly
as an array subscript into the kzalloc'd info struct:
  info->region_size[fm->region] = max(...);

A userspace caller supplying NPU_SET_IFM_REGION with param > 7 causes
a write up to 127*8 = 1016 bytes past the start of region_size[],
corrupting adjacent kernel heap data.

Fix by applying the same & 0x7 mask used by all other region
assignments.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-53172?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53172?

Apply the vendor's patch.

## Is CVE-2026-53172 being exploited?

There is no known exploitation of CVE-2026-53172 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-2026-53172 and fix it if it is affected.

What it is: CVE-2026-53172 is a high-severity memory corruption vulnerability in Linux kernel, published on 25 Jun 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-2026-53172 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-2026-53172/ (Markdown: https://insights.sbomify.com/CVE-2026-53172/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53172
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53172
- OSV: https://osv.dev/vulnerability/CVE-2026-53172

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53172/
Summaries are generated and may contain mistakes; the official description above is the record.