# CVE-2013-4891: Cross-site scripting in n/a

> Remote attackers can bypass XSS protection in CodeIgniter to execute scripts via unclosed HTML tags, affecting web applications using the framework.

- **Severity:** Medium 6.1 (`CVSS:3.0/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:** 21 Feb 2018
- **Updated:** 6 Aug 2024
- **Also known as:** GHSA-mq3g-6f5h-64x7

## What is CVE-2013-4891?

CVE-2013-4891 is a medium-severity cross-site scripting vulnerability in n/a, published on 21 Feb 2018. 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

The xss_clean function in CodeIgniter before 2.1.4 might allow remote attackers to bypass an intended protection mechanism and conduct cross-site scripting (XSS) attacks via an unclosed HTML tag.

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

## Which versions are affected by CVE-2013-4891?

It affects 1 product.


Products: Codeigniter Codeigniter.

## How do I fix CVE-2013-4891?

No fix has been published for CVE-2013-4891 yet. Limit exposure of the affected software until one is available.

## Is CVE-2013-4891 being exploited?

There is no known exploitation of CVE-2013-4891 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2025-54418](https://insights.sbomify.com/CVE-2025-54418/): CodeIgniter4's ImageMagick Handler has Command Injection Vulnerability (critical 9.8)
- [CVE-2023-32692](https://insights.sbomify.com/CVE-2023-32692/): Remote Code Execution Vulnerability in Validation Placeholders (critical 9.8)
- [CVE-2022-40824](https://insights.sbomify.com/CVE-2022-40824/): SQL injection in n/a (critical 9.8)
- [CVE-2022-40825](https://insights.sbomify.com/CVE-2022-40825/): SQL injection in n/a (critical 9.8)
- [CVE-2022-40826](https://insights.sbomify.com/CVE-2022-40826/): SQL injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2013-4891 and fix it if it is affected.

What it is: CVE-2013-4891 is a medium-severity cross-site scripting vulnerability in n/a, published on 21 Feb 2018. 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-2013-4891 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-2013-4891/ (Markdown: https://insights.sbomify.com/CVE-2013-4891/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2013-4891
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2013-4891
- OSV: https://osv.dev/vulnerability/CVE-2013-4891

---
From sbomify Insights: https://insights.sbomify.com/CVE-2013-4891/
Summaries are generated and may contain mistakes; the official description above is the record.