# CVE-2025-8843: NASM Netwide Assember outmacho.c macho_no_dead_strip heap-based overflow

> A heap-based buffer overflow in NASM allows local attackers to execute arbitrary code or cause denial of service via crafted input.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Aug 2025
- **Updated:** 11 Aug 2025
- **Also known as:** AZL-66210, AZL-66233, DEBIAN-CVE-2025-8843, GHSA-fr9x-hqv8-c4hf, UBUNTU-CVE-2025-8843

## What is CVE-2025-8843?

CVE-2025-8843 is a medium-severity memory corruption vulnerability in Nasm Netwide Assembler, published on 11 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was found in NASM Netwide Assember 2.17rc0. This affects the function macho_no_dead_strip of the file outmacho.c. The manipulation leads to heap-based buffer overflow. Local access is required to approach this attack. The exploit has been disclosed to the public and may be used.

Weakness: CWE-122 (Heap-based Buffer Overflow), CWE-787 (Out-of-bounds Write), CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer)

## Which versions are affected by CVE-2025-8843?

It affects 1 product.


Products: Nasm Netwide Assembler.

## How do I fix CVE-2025-8843?

No fix has been published for CVE-2025-8843 yet. Limit exposure of the affected software until one is available.

## Is CVE-2025-8843 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-8843 exists.

## Other vulnerabilities in Nasm Netwide Assembler

- [CVE-2004-1287](https://insights.sbomify.com/CVE-2004-1287/): Memory corruption in n/a (critical 10.0)
- [CVE-2020-24978](https://insights.sbomify.com/CVE-2020-24978/): Use after free in n/a (critical 9.8)
- [CVE-2008-7177](https://insights.sbomify.com/CVE-2008-7177/): Memory corruption in n/a (critical 9.3)
- [CVE-2023-31722](https://insights.sbomify.com/CVE-2023-31722/): Memory corruption in n/a (high 7.8)
- [CVE-2022-44370](https://insights.sbomify.com/CVE-2022-44370/): Memory corruption in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-8843 and fix it if it is affected.

What it is: CVE-2025-8843 is a medium-severity memory corruption vulnerability in Nasm Netwide Assembler, published on 11 Aug 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-8843 exists.

Affected product: Nasm Netwide Assembler. 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-2025-8843/ (Markdown: https://insights.sbomify.com/CVE-2025-8843/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-8843
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-8843
- OSV: https://osv.dev/vulnerability/CVE-2025-8843

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-8843/
Summaries are generated and may contain mistakes; the official description above is the record.