# CVE-2026-45348: pyLoad: Stored XSS in Downloads view via unsanitized link URL in packages.js template literal

> Attackers can execute arbitrary JavaScript in operator browsers via stored XSS in the downloads view, potentially leading to session hijacking or further compromise.

- **Severity:** High 8.7 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N`)
- **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 May 2026
- **Updated:** 28 May 2026
- **Also known as:** GHSA-fcjq-435v-jx94, PYSEC-2026-2994

## What is CVE-2026-45348?

CVE-2026-45348 is a high-severity cross-site scripting vulnerability in pyload, published on 28 May 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

pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev100, the packages.js template at src/pyload/webui/app/themes/modern/templates/js/packages.js:172 interpolates a stored link URL into a template literal inside single-quoted HTML and then writes the result to the DOM via $(div).html(html). No escaping runs between the API value and innerHTML. An attacker (Alice) who can submit a package link puts a single quote plus event handler into the URL, breaks out of the attribute, and executes JavaScript in every operator's browser that opens the downloads view. The theme does not set a Content Security Policy that restricts inline script or event handlers. This vulnerability is fixed in 0.5.0b3.dev100.

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

## Which versions are affected by CVE-2026-45348?

3 open source packages ship an affected version, including pyload-ng.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `pyload-ng` | PyPI | All versions to 0.5.0b3.dev99 | None |
| `pyload-ng` | PyPI | All versions to 0.5.0b3.dev99 | None |
| `pyload-ng` | PyPI | All versions to 0.5.0b3.dev99 | None |

## How do I fix CVE-2026-45348?

No fix has been published for CVE-2026-45348 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-45348 being exploited?

There is no known exploitation of CVE-2026-45348 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-45348 and fix it if it is affected.

What it is: CVE-2026-45348 is a high-severity cross-site scripting vulnerability in pyload, published on 28 May 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-45348 in the wild and no public exploit code.

Affected packages and fixed versions:
- pyload-ng (PyPI): affected all versions up to 0.5.0b3.dev99; no fix listed
- pyload-ng (PyPI): affected all versions up to 0.5.0b3.dev99; no fix listed
- pyload-ng (PyPI): affected all versions up to 0.5.0b3.dev99; 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-2026-45348/ (Markdown: https://insights.sbomify.com/CVE-2026-45348/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-45348
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-45348
- OSV: https://osv.dev/vulnerability/CVE-2026-45348

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-45348/
Summaries are generated and may contain mistakes; the official description above is the record.