# CVE-2026-64018: net: mana: validate rx_req_idx to prevent out-of-bounds array access

> An attacker with hardware control can trigger an out-of-bounds array access in the Linux kernel's MANA driver, potentially leading to code execution or system crashes.

- **Severity:** Critical 9.3 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 19 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-64018, DEBIAN-CVE-2026-64018, GHSA-r2vm-q278-6vpv, UBUNTU-CVE-2026-64018

## What is CVE-2026-64018?

CVE-2026-64018 is a critical memory corruption vulnerability in Linux kernel, published on 19 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:

net: mana: validate rx_req_idx to prevent out-of-bounds array access

In mana_hwc_rx_event_handler(), rx_req_idx is derived from
sge->address in DMA-coherent memory. In Confidential VMs
(SEV-SNP/TDX), this memory is shared unencrypted and HW can modify
WQE contents at any time. No bounds check exists on rx_req_idx,
which can lead to an out-of-bounds access into reqs[].

Add bounds check on rx_req_idx in mana_hwc_rx_event_handler() before
using it to index the reqs[] array.

Weakness: CWE-129 (Improper Validation of Array Index), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-64018?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64018?

Apply the vendor's patch.

## Is CVE-2026-64018 being exploited?

There is no known exploitation of CVE-2026-64018 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-2026-64018 and fix it if it is affected.

What it is: CVE-2026-64018 is a critical memory corruption vulnerability in Linux kernel, published on 19 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-2026-64018 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-2026-64018/ (Markdown: https://insights.sbomify.com/CVE-2026-64018/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64018
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64018
- OSV: https://osv.dev/vulnerability/CVE-2026-64018

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64018/
Summaries are generated and may contain mistakes; the official description above is the record.