# CVE-2026-104250: unstructured: Stored XSS via unescaped HTML generation

> Attackers can execute arbitrary scripts in a viewer's browser via unescaped HTML in the unstructured library, risking account takeover in document workflows.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/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:** Yes
- **Published:** 13 Oct 2026
- **Updated:** 14 Oct 2026
- **Also known as:** GHSA-v5mq-3xhg-98m9

## What is CVE-2026-104250?

CVE-2026-104250 is a medium-severity cross-site scripting vulnerability in Unstructured-IO unstructured, published on 13 Oct 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

The unstructured library provides open-source components for ingesting and pre-processing images and text documents, such as PDFs, HTML, Word docs, and many more. Prior to 0.24.1, partition_html(html_parser_version="v2") and the VLM partitioner can preserve untrusted document tags, attributes, text, and link targets in metadata.text_as_html, while elements_to_html() emits the result as an HTML document. The to_html() path in unstructured/documents/ontology.py does not escape output or reject unsafe URL schemes, allowing event-handler attributes, attribute breakout markup, and javascript: links to survive parsing. When the generated HTML or text_as_html is rendered in a browser, attacker-controlled script can execute in the viewer's origin, including in document-ingestion workflows where a privileged reviewer opens submitted content. This issue is fixed in version 0.24.1.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-116 (Improper Encoding or Escaping of Output)

## Which versions are affected by CVE-2026-104250?

2 open source packages ship an affected version, including unstructured.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `unstructured` | PyPI | All versions | 0.24.1 |
| `unstructured` | PyPI | All versions | 0.24.1 |

## How do I fix CVE-2026-104250?

Upgrade unstructured to 0.24.1 or later.

## Is CVE-2026-104250 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-104250 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-104250 and fix it if it is affected.

What it is: CVE-2026-104250 is a medium-severity cross-site scripting vulnerability in Unstructured-IO unstructured, published on 13 Oct 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: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-104250 exists.

Affected packages and fixed versions:
- unstructured (PyPI): affected all versions; fixed in 0.24.1
- unstructured (PyPI): affected all versions; fixed in 0.24.1

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-2026-104250/ (Markdown: https://insights.sbomify.com/CVE-2026-104250/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-104250
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-104250
- OSV: https://osv.dev/vulnerability/CVE-2026-104250

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-104250/
Summaries are generated and may contain mistakes; the official description above is the record.