# CVE-2011-5251: Open redirect in n/a

> Remote attackers can redirect users to malicious sites via the login page, facilitating phishing attacks against vBulletin forum users.

- **Severity:** Medium 5.8 (`AV:N/AC:M/Au:N/C:P/I:P/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:** 31 Dec 2012
- **Updated:** 17 Sep 2024
- **Also known as:** GHSA-5fjp-86vc-f4r2

## What is CVE-2011-5251?

CVE-2011-5251 is a medium-severity vulnerability in Vbulletin Vbulletin, published on 31 Dec 2012. 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

Open redirect vulnerability in forum/login.php in vBulletin 4.1.3 and earlier allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via the url parameter in a lostpw action.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2011-5251?

It affects 1 product.


Products: Vbulletin Vbulletin.

## How do I fix CVE-2011-5251?

No fix has been published for CVE-2011-5251 yet. Limit exposure of the affected software until one is available.

## Is CVE-2011-5251 being exploited?

There is no known exploitation of CVE-2011-5251 in the wild and no public exploit code.

## Other vulnerabilities in Vbulletin Vbulletin

- [CVE-2020-17496](https://insights.sbomify.com/CVE-2020-17496/): vBulletin PHP Module Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16759](https://insights.sbomify.com/CVE-2019-16759/): vBulletin PHP Module Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2025-48827](https://insights.sbomify.com/CVE-2025-48827/): vBulletin 5.0.0 through 5.7.5 and 6.0.0 through 6.0.3 allows unauthenticated users to invoke protected API controllers' methods when running (critical 10.0)
- [CVE-2023-25135](https://insights.sbomify.com/CVE-2023-25135/): Deserialization in n/a (critical 9.8)
- [CVE-2020-7373](https://insights.sbomify.com/CVE-2020-7373/): Code injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2011-5251 and fix it if it is affected.

What it is: CVE-2011-5251 is a medium-severity vulnerability in Vbulletin Vbulletin, published on 31 Dec 2012. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2011-5251 in the wild and no public exploit code.

Affected product: Vbulletin Vbulletin. 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-2011-5251/ (Markdown: https://insights.sbomify.com/CVE-2011-5251/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2011-5251
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2011-5251
- OSV: https://osv.dev/vulnerability/CVE-2011-5251

---
From sbomify Insights: https://insights.sbomify.com/CVE-2011-5251/
Summaries are generated and may contain mistakes; the official description above is the record.