# CVE-2026-51400: Memory corruption in n/a

> A local attacker can execute arbitrary code in Vim via a memory corruption flaw in the vms_fixfilename function.

- **Severity:** High 8.4 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 4 Aug 2026
- **Updated:** 5 Aug 2026
- **Also known as:** GHSA-c4x9-mpg2-r897

## What is CVE-2026-51400?

CVE-2026-51400 is a high-severity memory corruption vulnerability in Vim Vim, published on 4 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

An issue in Vim Project v9.2.0389 and earlier allows a local attacker to execute arbitrary code via the vms_fixfilename() function within file vim/src/os_vms.c

Weakness: CWE-401 (Missing Release of Memory after Effective Lifetime)

## Which versions are affected by CVE-2026-51400?

It affects 1 product.


Products: Vim Vim.

## How do I fix CVE-2026-51400?

No fix has been published for CVE-2026-51400 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-51400 being exploited?

There is no known exploitation of CVE-2026-51400 in the wild and no public exploit code.

## Other vulnerabilities in Vim Vim

- [CVE-2020-20703](https://insights.sbomify.com/CVE-2020-20703/): Memory corruption in n/a (critical 9.8)
- [CVE-2017-6349](https://insights.sbomify.com/CVE-2017-6349/): Integer overflow in n/a (critical 9.8)
- [CVE-2017-6350](https://insights.sbomify.com/CVE-2017-6350/): Integer overflow in n/a (critical 9.8)
- [CVE-2017-5953](https://insights.sbomify.com/CVE-2017-5953/): Integer overflow in n/a (critical 9.8)
- [CVE-2008-3075](https://insights.sbomify.com/CVE-2008-3075/): Command injection in n/a (critical 9.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-51400 and fix it if it is affected.

What it is: CVE-2026-51400 is a high-severity memory corruption vulnerability in Vim Vim, published on 4 Aug 2026. 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-2026-51400 in the wild and no public exploit code.

Affected product: Vim Vim. 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-2026-51400/ (Markdown: https://insights.sbomify.com/CVE-2026-51400/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-51400
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-51400
- OSV: https://osv.dev/vulnerability/CVE-2026-51400

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-51400/
Summaries are generated and may contain mistakes; the official description above is the record.