# CVE-2020-27176: Cross-site scripting in n/a

> Mutation XSS in Mark Text allows remote code execution via source code mode HTML parsing.

- **Severity:** High 8.3 (`CVSS:3.1/AC:H/AV:N/A:H/C:H/I:H/PR:N/S:C/UI:R`)
- **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:** 16 Oct 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-q367-49gp-hvp2

## What is CVE-2020-27176?

CVE-2020-27176 is a high-severity cross-site scripting vulnerability in n/a, published on 16 Oct 2020. 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

Mutation XSS exists in Mark Text through 0.16.2 that leads to Remote Code Execution. NOTE: this might be considered a duplicate of CVE-2020-26870; however, it can also be considered an issue in the design of the "source code mode" feature, which parses HTML even though HTML support is not one of the primary advertised roles of the product.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2020-27176?

It affects 1 product.


Products: Marktext Marktext.

## How do I fix CVE-2020-27176?

No fix has been published for CVE-2020-27176 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-27176 being exploited?

There is no known exploitation of CVE-2020-27176 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2022-25069](https://insights.sbomify.com/CVE-2022-25069/): Cross-site scripting in n/a (critical 9.6)
- [CVE-2021-29996](https://insights.sbomify.com/CVE-2021-29996/): Cross-site scripting in n/a (critical 9.6)
- [CVE-2022-24123](https://insights.sbomify.com/CVE-2022-24123/): Cross-site scripting in n/a (critical 9.0)
- [CVE-2023-2318](https://insights.sbomify.com/CVE-2023-2318/): MarkText DOM-Based Cross-site Scripting leading to Remote Code Execution (high 8.6)
- [CVE-2022-21158](https://insights.sbomify.com/CVE-2022-21158/): Cross-site scripting in MarkText (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-27176 and fix it if it is affected.

What it is: CVE-2020-27176 is a high-severity cross-site scripting vulnerability in n/a, published on 16 Oct 2020. 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-2020-27176 in the wild and no public exploit code.

Affected product: n/a. 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-2020-27176/ (Markdown: https://insights.sbomify.com/CVE-2020-27176/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-27176
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-27176
- OSV: https://osv.dev/vulnerability/CVE-2020-27176

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-27176/
Summaries are generated and may contain mistakes; the official description above is the record.