# CVE-2026-109828: libsndfile WAV Parsing wavlike.c wavlike_subchunk_parse uninitialized variable

> Remote attackers can exploit an uninitialized variable in libsndfile's WAV parser to potentially execute code or cause denial of service.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 13 Oct 2026
- **Updated:** 13 Oct 2026
- **Also known as:** AZL-108036, BELL-CVE-2026-109828, DEBIAN-CVE-2026-109828, ECHO-db1c-5134-4939, GHSA-f48f-2357-x2fh, UBUNTU-CVE-2026-109828

## What is CVE-2026-109828?

CVE-2026-109828 is a medium-severity memory corruption vulnerability in libsndfile, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A vulnerability was found in libsndfile up to 1.2.2. This issue affects the function wavlike_subchunk_parse of the file src/wavlike.c of the component WAV Parsing. Performing a manipulation results in use of uninitialized variable. Remote exploitation of the attack is possible. The exploit has been made public and could be used. The project was informed of the problem early through an issue report but has not responded yet.

Weakness: CWE-457 (Use of Uninitialized Variable), CWE-453 (Insecure Default Variable Initialization)

## Which versions are affected by CVE-2026-109828?


## How do I fix CVE-2026-109828?

No fix published yet.

## Is CVE-2026-109828 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109828 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-109828 and fix it if it is affected.

What it is: CVE-2026-109828 is a medium-severity memory corruption vulnerability in libsndfile, published on 13 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109828 exists.

Affected product: libsndfile. 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-2026-109828/ (Markdown: https://insights.sbomify.com/CVE-2026-109828/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-109828
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-109828
- OSV: https://osv.dev/vulnerability/CVE-2026-109828

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-109828/
Summaries are generated and may contain mistakes; the official description above is the record.