# CVE-2026-49492: Markdown Preview Enhanced OS Command Injection in External File and Link Opening

> Attackers can execute arbitrary OS commands on Windows by crafting a markdown document with malicious attributes in Markdown Preview Enhanced.

- **Severity:** High 8.6 (`CVSS:4.0/AV:N/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:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 5 Jun 2026
- **Updated:** 8 Jun 2026
- **Also known as:** GHSA-3vxg-8vgp-994w

## What is CVE-2026-49492?

CVE-2026-49492 is a high-severity command injection vulnerability in shd101wyy Markdown Preview Enhanced, published on 5 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Markdown Preview Enhanced before 0.8.28 opens external files and links from the preview through a shell and does not validate untrusted inputs taken from the markdown document - the diagram filename attribute, imported file paths, and the latex_engine code-chunk attribute. On Windows, a crafted markdown document can inject operating system commands that execute when the document is previewed. Fixed in 0.8.28 by passing these inputs as literal arguments instead of through a shell and validating them before use.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2026-49492?


## How do I fix CVE-2026-49492?

No fix has been published for CVE-2026-49492 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-49492 being exploited?

There is no known exploitation of CVE-2026-49492 in the wild and no public exploit code.

Public exploit code:

- https://github.com/byte16384/CVE-2026-49492-PoC (github_poc): https://github.com/byte16384/CVE-2026-49492-PoC

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49492 and fix it if it is affected.

What it is: CVE-2026-49492 is a high-severity command injection vulnerability in shd101wyy Markdown Preview Enhanced, published on 5 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-49492 in the wild and no public exploit code.

Affected product: shd101wyy Markdown Preview Enhanced. 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-2026-49492/ (Markdown: https://insights.sbomify.com/CVE-2026-49492/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49492
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49492
- OSV: https://osv.dev/vulnerability/CVE-2026-49492

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-49492/
Summaries are generated and may contain mistakes; the official description above is the record.