# CVE-2026-64304: crypto: qat - validate RSA CRT component lengths

> A buffer overflow in the Linux kernel QAT driver allows attackers to corrupt memory and potentially execute code or escalate privileges via crafted RSA keys.

- **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 Jul 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-64304, DEBIAN-CVE-2026-64304, GHSA-63x3-xxqc-x6vr, ROOT-OS-DEBIAN-12-CVE-2026-64304, ROOT-OS-UBUNTU-2204-CVE-2026-64304, UBUNTU-CVE-2026-64304

## What is CVE-2026-64304?

CVE-2026-64304 is a high-severity memory corruption 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:

crypto: qat - validate RSA CRT component lengths

The generic RSA key parser (rsa_helper.c) bounds each CRT component (p,
q, dp, dq, qinv) by the modulus size n_sz, but qat_rsa_setkey_crt()
allocates half-size DMA buffers (key_sz / 2) and right-aligns each
component with:

    memcpy(dst + half_key_sz - len, src, len)

When a CRT component is larger than half_key_sz the subtraction
underflows and memcpy writes past the DMA buffer, causing memory
corruption.

Add a len > half_key_sz check next to the existing !len check for each
of the five CRT components so the driver falls back to the non-CRT path
instead of writing out of bounds.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-64304?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-64304?

Apply the vendor's patch.

## Is CVE-2026-64304 being exploited?

There is no known exploitation of CVE-2026-64304 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-2026-64304 and fix it if it is affected.

What it is: CVE-2026-64304 is a high-severity memory corruption 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-2026-64304 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-2026-64304/ (Markdown: https://insights.sbomify.com/CVE-2026-64304/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64304
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64304
- OSV: https://osv.dev/vulnerability/CVE-2026-64304

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64304/
Summaries are generated and may contain mistakes; the official description above is the record.