# CVE-2022-39338: Stored cross site scripting (XSS) vulnerability via Authorization Endpoint in user_oidc

> Stored XSS in Nextcloud user_oidc allows attackers to execute scripts in Safari via unvalidated discovery URLs, mitigated by upgrading.

- **Severity:** Low 3.5 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 25 Nov 2022
- **Updated:** 23 Apr 2025
- **Also known as:** GHSA-5fpw-795h-rg57

## What is CVE-2022-39338?

CVE-2022-39338 is a low-severity cross-site scripting vulnerability in nextcloud security-advisories, published on 25 Nov 2022. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

### Official description

user_oidc is an OpenID Connect user backend for Nextcloud. Versions prior to 1.2.1 did not properly validate discovery urls which may lead to a stored cross site scripting attack vector. The impact is limited due to the restrictive CSP that is applied on this endpoint. Additionally this vulnerability has only been shown to be exploitable in the Safari web browser. This issue has been addressed in version 1.2.1. Users are advised to upgrade. Users unable to upgrade should urge their users to avoid using the Safari web browser.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2022-39338?

It affects 1 product.


Products: Nextcloud Openid Connect User Backend.

## How do I fix CVE-2022-39338?

No fix has been published for CVE-2022-39338 yet. Limit exposure of the affected software until one is available.

## Is CVE-2022-39338 being exploited?

There is no known exploitation of CVE-2022-39338 in the wild and no public exploit code.

## Other vulnerabilities in nextcloud security-advisories

- [CVE-2022-39339](https://insights.sbomify.com/CVE-2022-39339/): Cleartext Transmission of Sensitive Information in user_oidc (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-39338 and fix it if it is affected.

What it is: CVE-2022-39338 is a low-severity cross-site scripting vulnerability in nextcloud security-advisories, published on 25 Nov 2022. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2022-39338 in the wild and no public exploit code.

Affected product: nextcloud security-advisories. 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-2022-39338/ (Markdown: https://insights.sbomify.com/CVE-2022-39338/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-39338
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-39338
- OSV: https://osv.dev/vulnerability/CVE-2022-39338

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-39338/
Summaries are generated and may contain mistakes; the official description above is the record.