# CVE-2015-2940: Cross-site request forgery in n/a

> A CSRF vulnerability in the MediaWiki CheckUser extension allows attackers to hijack user sessions and retrieve sensitive information.

- **Severity:** Medium 6.8 (`AV:N/AC:M/Au:N/C:P/I:P/A:P`)
- **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:** 13 Apr 2015
- **Updated:** 6 Aug 2024
- **Also known as:** DEBIAN-CVE-2015-2940, GHSA-g77q-mpv6-8w22

## What is CVE-2015-2940?

CVE-2015-2940 is a medium-severity vulnerability in n/a, published on 13 Apr 2015. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Cross-site request forgery (CSRF) vulnerability in the CheckUser extension for MediaWiki allows remote attackers to hijack the authentication of certain users for requests that retrieve sensitive user information via unspecified vectors.

Weakness: CWE-352 (Cross-Site Request Forgery)

## Which versions are affected by CVE-2015-2940?

It affects 1 product.


Products: Mediawiki Checkuser.

## How do I fix CVE-2015-2940?

Upgrade to a fixed version.

## Is CVE-2015-2940 being exploited?

There is no known exploitation of CVE-2015-2940 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2019-18611](https://insights.sbomify.com/CVE-2019-18611/): Information disclosure in n/a (medium 6.5)
- [CVE-2019-16529](https://insights.sbomify.com/CVE-2019-16529/): Information disclosure in n/a (medium 5.3)
- [CVE-2026-34090](https://insights.sbomify.com/CVE-2026-34090/): Suggested investigations: Handle suppressed usernames (medium 4.8)
- [CVE-2025-61658](https://insights.sbomify.com/CVE-2025-61658/): Special:GlobalContributions shows edits on wikis the viewer doesn't have access to (low 1.3)
- [CVE-2025-61648](https://insights.sbomify.com/CVE-2025-61648/): Stored XSS through system messages in CheckUser (not scored)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2015-2940 and fix it if it is affected.

What it is: CVE-2015-2940 is a medium-severity vulnerability in n/a, published on 13 Apr 2015. 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-2015-2940 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-2015-2940/ (Markdown: https://insights.sbomify.com/CVE-2015-2940/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2015-2940
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2015-2940
- OSV: https://osv.dev/vulnerability/CVE-2015-2940

---
From sbomify Insights: https://insights.sbomify.com/CVE-2015-2940/
Summaries are generated and may contain mistakes; the official description above is the record.