# CVE-2020-8031: obs: Stored XSS

> Remote attackers can inject malicious JavaScript into markdown content in Open Build Service, compromising confidentiality and integrity.

- **Severity:** Medium 6.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:L/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:** Yes
- **Published:** 11 Feb 2021
- **Updated:** 16 Sep 2024
- **Also known as:** DEBIAN-CVE-2020-8031, GHSA-6g6q-c7q8-8r7m, OESA-2022-1577, UBUNTU-CVE-2020-8031

## What is CVE-2020-8031?

CVE-2020-8031 is a medium-severity cross-site scripting vulnerability in openSUSE Open Build Service, published on 11 Feb 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

A Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Open Build Service allows remote attackers to store JS code in markdown that is not properly escaped, impacting confidentiality and integrity. This issue affects: Open Build Service versions prior to 2.10.8.

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

## Which versions are affected by CVE-2020-8031?

It affects 1 product.


Products: Opensuse Open Build Service.

## How do I fix CVE-2020-8031?

Upgrade to a fixed version.

## Is CVE-2020-8031 being exploited?

There is no known exploitation of CVE-2020-8031 in the wild and no public exploit code.

## Other vulnerabilities in openSUSE Open Build Service

- [CVE-2022-21949](https://insights.sbomify.com/CVE-2022-21949/): Multiple XXE vulnerabilities in OBS (high 8.8)
- [CVE-2013-3703](https://insights.sbomify.com/CVE-2013-3703/): No write permission check in change_role command (high 8.8)
- [CVE-2014-0594](https://insights.sbomify.com/CVE-2014-0594/): CSRF protection incorrectly disabled (high 8.8)
- [CVE-2021-36777](https://insights.sbomify.com/CVE-2021-36777/): login-proxy sends password to attacker-provided domain (high 8.1)
- [CVE-2011-3178](https://insights.sbomify.com/CVE-2011-3178/): openbuildservice webui code injection (high 8.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-8031 and fix it if it is affected.

What it is: CVE-2020-8031 is a medium-severity cross-site scripting vulnerability in openSUSE Open Build Service, published on 11 Feb 2021. 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-2020-8031 in the wild and no public exploit code.

Affected product: openSUSE Open Build Service. 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-2020-8031/ (Markdown: https://insights.sbomify.com/CVE-2020-8031/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-8031
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-8031
- OSV: https://osv.dev/vulnerability/CVE-2020-8031

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From sbomify Insights: https://insights.sbomify.com/CVE-2020-8031/
Summaries are generated and may contain mistakes; the official description above is the record.