# CVE-2026-111270: libmodplug through 0.8.9.1 Heap Out-of-Bounds Write via CSoundFile::ReadDSM

> Attackers can cause heap corruption and potential code execution by providing a crafted DSM file to applications using libmodplug.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 15 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-110351, DEBIAN-CVE-2026-111270, ECHO-d378-2d1f-97fb, GHSA-rxvf-jg5h-5fv5, UBUNTU-CVE-2026-111270

## What is CVE-2026-111270?

CVE-2026-111270 is a medium-severity memory corruption vulnerability in Konstanty Bialkowski libmodplug, published on 15 Oct 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

libmodplug through 0.8.9.1 contains a heap-based out-of-bounds write in CSoundFile::ReadDSM() in src/load_dsm.cpp because nPat is never checked against MAX_PATTERNS. Attackers can supply a crafted DSM file with over 240 PATT chunks or a wrapping patt_len value to corrupt heap memory and crash the consuming process.

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

## Which versions are affected by CVE-2026-111270?


## How do I fix CVE-2026-111270?

Upgrade to a fixed version.

## Is CVE-2026-111270 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-111270 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-111270 and fix it if it is affected.

What it is: CVE-2026-111270 is a medium-severity memory corruption vulnerability in Konstanty Bialkowski libmodplug, published on 15 Oct 2026. It can only be exploited from the same machine or local network, 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-2026-111270 exists.

Affected product: Konstanty Bialkowski libmodplug. 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-2026-111270/ (Markdown: https://insights.sbomify.com/CVE-2026-111270/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-111270
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-111270
- OSV: https://osv.dev/vulnerability/CVE-2026-111270

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-111270/
Summaries are generated and may contain mistakes; the official description above is the record.