# CVE-2025-52939: Potential heap-buffer overflow vulnerability in NotepadNext

> A heap-buffer overflow in NotepadNext's Lua modules allows attackers to execute arbitrary code or crash the application via crafted input.

- **Severity:** Critical 9.4 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/S:N/AU:Y/R:U/V:C/RE:M/U:Red`)
- **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:** 23 Jun 2025
- **Updated:** 23 Jun 2025
- **Also known as:** AZL-64404, GHSA-hhj4-3c38-ppmf

## What is CVE-2025-52939?

CVE-2025-52939 is a critical memory corruption vulnerability in dail8859 NotepadNext, published on 23 Jun 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Out-of-bounds Write vulnerability in dail8859 NotepadNext (src/lua/src modules). This vulnerability is associated with program files ldebug.C, lvm.C.

This issue affects NotepadNext: through v0.11.

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

## Which versions are affected by CVE-2025-52939?


## How do I fix CVE-2025-52939?

Apply the vendor's patch.

## Is CVE-2025-52939 being exploited?

There is no known exploitation of CVE-2025-52939 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-52939 and fix it if it is affected.

What it is: CVE-2025-52939 is a critical memory corruption vulnerability in dail8859 NotepadNext, published on 23 Jun 2025. 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-2025-52939 in the wild and no public exploit code.

Affected product: dail8859 NotepadNext. 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-2025-52939/ (Markdown: https://insights.sbomify.com/CVE-2025-52939/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-52939
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-52939
- OSV: https://osv.dev/vulnerability/CVE-2025-52939

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-52939/
Summaries are generated and may contain mistakes; the official description above is the record.