# CVE-2026-63838: ASoC: rsnd: Fix potential out-of-bounds access of component_dais[]

> A local attacker can trigger an out-of-bounds memory access in the Linux kernel's Renesas sound driver, potentially causing a crash or arbitrary code execution.

- **Severity:** Not scored
- **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 Jul 2026
- **Also known as:** BELL-CVE-2026-63838, DEBIAN-CVE-2026-63838, GHSA-vfg9-hvpm-5mgj, UBUNTU-CVE-2026-63838

## What is CVE-2026-63838?

CVE-2026-63838 is a memory corruption vulnerability in Linux, 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:

ASoC: rsnd: Fix potential out-of-bounds access of component_dais[]

component_dais[RSND_MAX_COMPONENT] is initially zero-initialized
and later populated in rsnd_dai_of_node(). However, the existing boundary check:
  if (i >= RSND_MAX_COMPONENT)

does not guarantee that the last valid element remains zero. As a result,
the loop can rely on component_dais[RSND_MAX_COMPONENT] being zero,
which may lead to an out-of-bounds access.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

## Which versions are affected by CVE-2026-63838?


## How do I fix CVE-2026-63838?

Apply the vendor's patch.

## Is CVE-2026-63838 being exploited?

There is no known exploitation of CVE-2026-63838 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-63838 and fix it if it is affected.

What it is: CVE-2026-63838 is a memory corruption vulnerability in Linux, 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-2026-63838 in the wild and no public exploit code.

Affected product: Linux. 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-2026-63838/ (Markdown: https://insights.sbomify.com/CVE-2026-63838/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-63838
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-63838
- OSV: https://osv.dev/vulnerability/CVE-2026-63838

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-63838/
Summaries are generated and may contain mistakes; the official description above is the record.