CVE-2017-20262 — Joomla! Component Ajax Quiz SQL Injection

CVE-2017-20262 details an unauthenticated SQL injection vulnerability affecting Joomla! Component Ajax Quiz version 1.8. Threat actors can exploit this weakness by crafting specific GET requests to the index.php endpoint, utilizing the option=com_ajaxquiz and view=ajaxquiz parameters. By injecting malicious SQL code into the cid parameter, attackers can execute arbitrary SQL queries on the underlying database. This allows for the extraction of sensitive database information, including table names, column structures, and potentially confidential data, posing a significant risk to data confidentiality and integrity. The vulnerability stems from improper neutralization of special elements used in SQL commands.

Attack Chain

1. Reconnaissance & Target Identification: Attacker identifies a Joomla! instance running the vulnerable Ajax Quiz component version 1.8, often through automated scanning or public information.
2. Vulnerability Discovery: Attacker identifies the cid parameter in GET requests to index.php?option=com_ajaxquiz&view=ajaxquiz as a potential SQL injection point, either by probing or using known exploit patterns.
3. Initial SQL Injection: Attacker crafts a malicious GET request, such as GET /index.php?option=com_ajaxquiz&view=ajaxquiz&cid=1%20UNION%20SELECT%20NULL,user()--+, injecting an SQL payload into the cid parameter.
4. Arbitrary Query Execution: The vulnerable component processes the request without properly sanitizing the cid parameter, leading to the execution of the injected SQL query by the backend database.
5. Database Schema Enumeration: Attacker sends follow-up requests with increasingly complex SQL payloads to enumerate database metadata, including table names and column structures, typically using information_schema or similar system tables.
6. Sensitive Data Exfiltration: Using the obtained database schema, the attacker crafts further SQL queries to extract sensitive information, such as user credentials, personal data, or proprietary business data from specific tables.
7. Impact: Compromised sensitive data is extracted from the database, leading to potential data breaches, unauthorized access, and further exploitation of the affected organization.

Impact

Successful exploitation of CVE-2017-20262 grants unauthenticated attackers the ability to execute arbitrary SQL queries on the backend database. This directly leads to the compromise of sensitive information, such as user data, authentication credentials, and proprietary business logic stored within the database. The exfiltration of such data can result in significant financial losses, reputational damage, regulatory penalties, and potential for further unauthorized access to other systems or accounts, severely impacting the affected organization and its customers.

Recommendation

• Immediately update or disable the Joomla! Component Ajax Quiz 1.8 as described in CVE-2017-20262 to prevent exploitation.
• Deploy the Sigma rule "Detects CVE-2017-20262 Exploitation — Joomla! Ajax Quiz SQL Injection" to your SIEM to identify active exploitation attempts against your web servers.
• Enable comprehensive web server logging (category webserver) to ensure visibility into HTTP requests, including full URI-stem and URI-query fields, for proper detection rule activation.