# CVE-2026-38949: Cross-site scripting in n/a

> Attackers can inject arbitrary code via the image content creation endpoint in HTMLy, potentially executing scripts in user browsers.

- **Severity:** High 8.9 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 28 Apr 2026
- **Updated:** 10 May 2026
- **Also known as:** GHSA-42cc-qc2r-r9fj

## What is CVE-2026-38949?

CVE-2026-38949 is a high-severity cross-site scripting vulnerability in n/a, published on 28 Apr 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Cross-Site Scripting (XSS) vulnerability exists in HTMLy version 3.1.1 in the content creation functionality at the /add/content?type=image endpoint. The application fails to properly sanitize user input, allowing injection of arbitrary code

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

## Which versions are affected by CVE-2026-38949?


## How do I fix CVE-2026-38949?

No fix has been published for CVE-2026-38949 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-38949 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-38949 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-38949 and fix it if it is affected.

What it is: CVE-2026-38949 is a high-severity cross-site scripting vulnerability in n/a, published on 28 Apr 2026. Any signed-in user can exploit it over the network, 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-2026-38949 exists.

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-2026-38949/ (Markdown: https://insights.sbomify.com/CVE-2026-38949/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-38949
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-38949
- OSV: https://osv.dev/vulnerability/CVE-2026-38949

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-38949/
Summaries are generated and may contain mistakes; the official description above is the record.