# CVE-2026-89266: stb_vorbis through 1.22 heap buffer overflow via codebook multiplicands

> Attackers can trigger heap buffer overflow via malicious Ogg Vorbis files, potentially leading to code execution or crashes in applications using stb_vorbis.

- **Severity:** High 8.8 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Sep 2026
- **Updated:** 24 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-89266, GHSA-4hj2-h365-qx39, UBUNTU-CVE-2026-89266

## What is CVE-2026-89266?

CVE-2026-89266 is a high-severity memory corruption vulnerability in nothings stb_vorbis, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

stb_vorbis through 1.22 contains a heap buffer overflow in start_decoder() where the codebook multiplicands allocation size is truncated from size_t to int. Attackers can craft a malicious Ogg Vorbis file with large entries and dimensions values to trigger out-of-bounds writes, causing process crashes or heap corruption.

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

## Which versions are affected by CVE-2026-89266?


## How do I fix CVE-2026-89266?

No fix has been published for CVE-2026-89266 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-89266 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-89266 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89266 and fix it if it is affected.

What it is: CVE-2026-89266 is a high-severity memory corruption vulnerability in nothings stb_vorbis, published on 11 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-89266 exists.

Affected product: nothings stb_vorbis. 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-2026-89266/ (Markdown: https://insights.sbomify.com/CVE-2026-89266/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89266
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89266
- OSV: https://osv.dev/vulnerability/CVE-2026-89266

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89266/
Summaries are generated and may contain mistakes; the official description above is the record.