# CVE-2011-0508: Cross-site scripting in n/a

> Remote attackers can inject arbitrary web script or HTML via the X_FORWARDED_FOR header in Contao CMS comments, potentially compromising user sessions.

- **Severity:** Medium 4.3 (`AV:N/AC:M/Au:N/C:N/I:P/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Jan 2011
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-gfg7-fg26-2g7j

## What is CVE-2011-0508?

CVE-2011-0508 is a medium-severity cross-site scripting vulnerability in n/a, published on 20 Jan 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Cross-site scripting (XSS) vulnerability in system/modules/comments/Comments.php in Contao CMS 2.9.2, and possibly other versions before 2.9.3, allows remote attackers to inject arbitrary web script or HTML via the HTTP X_FORWARDED_FOR header, which is stored by system/libraries/Environment.php but not properly handled by a comments action to main.php.

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

## Which versions are affected by CVE-2011-0508?

It affects 1 product.


Products: Contao Contao Cms.

## How do I fix CVE-2011-0508?

No fix has been published for CVE-2011-0508 yet. Limit exposure of the affected software until one is available.

## Is CVE-2011-0508 being exploited?

There is no known exploitation of CVE-2011-0508 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2014-1860](https://insights.sbomify.com/CVE-2014-1860/): Deserialization in n/a (critical 9.8)
- [CVE-2017-16558](https://insights.sbomify.com/CVE-2017-16558/): Contao SQL injection in the backend and listing module (critical 9.8)
- [CVE-2019-10641](https://insights.sbomify.com/CVE-2019-10641/): Contao Does Not Invalidate Existing Sessions When Password Changes (critical 9.8)
- [CVE-2019-10643](https://insights.sbomify.com/CVE-2019-10643/): Contao Does Not Expire Tokens Correctly (critical 9.8)
- [CVE-2019-10642](https://insights.sbomify.com/CVE-2019-10642/): Contao CSRF Token Bypass (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2011-0508 and fix it if it is affected.

What it is: CVE-2011-0508 is a medium-severity cross-site scripting vulnerability in n/a, published on 20 Jan 2011. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2011-0508 in the wild and no public exploit code.

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-2011-0508/ (Markdown: https://insights.sbomify.com/CVE-2011-0508/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-0508
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-0508
- OSV: https://osv.dev/vulnerability/CVE-2011-0508

---
From sbomify Insights: https://insights.sbomify.com/CVE-2011-0508/
Summaries are generated and may contain mistakes; the official description above is the record.