# CVE-2022-25849: Cross-site Scripting (XSS)

> An attacker can inject malicious scripts via the href attribute in markdown parsing, potentially executing code in the victim's browser.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A: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:** 26 Oct 2022
- **Updated:** 9 May 2025
- **Also known as:** GHSA-4r9g-w48q-8jwm

## What is CVE-2022-25849?

CVE-2022-25849 is a medium-severity cross-site scripting vulnerability in joyqi/hyper-down, published on 26 Oct 2022. 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

The package joyqi/hyper-down from 0.0.0 are vulnerable to Cross-site Scripting (XSS) because the module of parse markdown does not filter the href attribute very well.

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

## Which versions are affected by CVE-2022-25849?

2 open source packages ship an affected version, including joyqi/hyper-down. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `joyqi/hyper-down` | Packagist | All versions to 2.4.27 | None |
| `joyqi/hyper-down` | Packagist | All versions to 2.4.27 | None |

Products: Hyperdown Project Hyperdown.

## How do I fix CVE-2022-25849?

No fix has been published for CVE-2022-25849 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-25849 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-25849 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-25849 and fix it if it is affected.

What it is: CVE-2022-25849 is a medium-severity cross-site scripting vulnerability in joyqi/hyper-down, published on 26 Oct 2022. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-25849 exists.

Affected packages and fixed versions:
- joyqi/hyper-down (Packagist): affected all versions up to 2.4.27; no fix listed
- joyqi/hyper-down (Packagist): affected all versions up to 2.4.27; no fix listed

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-2022-25849/ (Markdown: https://insights.sbomify.com/CVE-2022-25849/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-25849
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-25849
- OSV: https://osv.dev/vulnerability/CVE-2022-25849

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-25849/
Summaries are generated and may contain mistakes; the official description above is the record.