# CVE-2026-59858: Vim: Arbitrary Code Execution via C Omni-Completion

> Attackers can execute arbitrary code by tricking users into opening a malicious C file with a crafted tags file, triggering unsafe command execution in Vim.

- **Severity:** High 8.4 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/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:** 9 Jul 2026
- **Updated:** 14 Jul 2026
- **Also known as:** ALPINE-CVE-2026-59858, BELL-CVE-2026-59858, CLSA-2026-1784036814, CLSA-2026-1784038367, CLSA-2026-1784042868, CLSA-2026-1784799349, CLSA-2026-1784799471, CLSA-2026-1784799711, CLSA-2026-1784802165, CLSA-2026-1784807557, CLSA-2026-1786353169, DEBIAN-CVE-2026-59858, ECHO-60cb-ca68-ea06, GHSA-mf92-v4xw-j45x, MINI-jj46-p349-6r9v, ROOT-OS-DEBIAN-11-CVE-2026-59858, ROOT-OS-DEBIAN-12-CVE-2026-59858, UBUNTU-CVE-2026-59858

## What is CVE-2026-59858?

CVE-2026-59858 is a high-severity code injection vulnerability in Vim Vim, published on 9 Jul 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

Vim is an open source, command line text editor. Prior to 9.2.0735, the C omni-completion script in runtime/autoload/ccomplete.vim interpolates the typeref: or typename: extension field of a tags entry, without escaping, into a :vimgrep pattern that is run through :execute. Because :vimgrep honors the bar as a command separator, a crafted tag field can close the search pattern and append an arbitrary Ex command; opening a hostile .c file whose project tags file contains such an entry and invoking C omni-completion runs that command as the editing user. This issue is fixed in version 9.2.0735.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2026-59858?

It affects 1 product.


Products: Vim Vim.

## How do I fix CVE-2026-59858?

Upgrade to a fixed version.

## Is CVE-2026-59858 being exploited?

There is no known exploitation of CVE-2026-59858 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-2026-59858 and fix it if it is affected.

What it is: CVE-2026-59858 is a high-severity code injection vulnerability in Vim Vim, published on 9 Jul 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: There is no known exploitation of CVE-2026-59858 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-2026-59858/ (Markdown: https://insights.sbomify.com/CVE-2026-59858/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-59858
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-59858
- OSV: https://osv.dev/vulnerability/CVE-2026-59858

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-59858/
Summaries are generated and may contain mistakes; the official description above is the record.