# CVE-2021-27310: Cross-site scripting in n/a

> Unauthenticated attackers can execute arbitrary scripts in victim browsers via the language parameter in Clansphere CMS.

- **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:** No
- **Published:** 23 Mar 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-gwcx-pjgx-wqm5

## What is CVE-2021-27310?

CVE-2021-27310 is a medium-severity cross-site scripting vulnerability in n/a, published on 23 Mar 2021. 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

Clansphere CMS 2011.4 allows unauthenticated reflected XSS via "language" parameter.

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

## Which versions are affected by CVE-2021-27310?

It affects 1 product.


Products: Csphere Clansphere.

## How do I fix CVE-2021-27310?

No fix has been published for CVE-2021-27310 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-27310 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-27310 exists.

Public exploit code:

- Clansphere CMS 2011.4 - Cross-Site Scripting (nuclei): http/cves/2021/CVE-2021-27310.yaml

## Other vulnerabilities in n/a

- [CVE-2012-10034](https://insights.sbomify.com/CVE-2012-10034/): ClanSphere 2011.3 Local File Inclusion via cs_lang Cookie (high 8.7)
- [CVE-2010-1865](https://insights.sbomify.com/CVE-2010-1865/): SQL injection in n/a (high 7.5)
- [CVE-2022-43119](https://insights.sbomify.com/CVE-2022-43119/): Cross-site scripting in n/a (medium 6.1)
- [CVE-2021-27309](https://insights.sbomify.com/CVE-2021-27309/): Cross-site scripting in n/a (medium 6.1)
- [CVE-2011-3714](https://insights.sbomify.com/CVE-2011-3714/): Information disclosure in n/a (medium 5.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-27310 and fix it if it is affected.

What it is: CVE-2021-27310 is a medium-severity cross-site scripting vulnerability in n/a, published on 23 Mar 2021. 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-2021-27310 exists.

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-2021-27310/ (Markdown: https://insights.sbomify.com/CVE-2021-27310/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-27310
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-27310
- OSV: https://osv.dev/vulnerability/CVE-2021-27310

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-27310/
Summaries are generated and may contain mistakes; the official description above is the record.