SQL Injection Vulnerability in ASP-CMS commentList.asp

ASP-CMS contains a critical SQL injection vulnerability in the commentList.asp endpoint, identified as CVE-2019-25765. This flaw allows unauthenticated remote attackers to execute arbitrary SQL queries by manipulating the id parameter within GET requests. The vulnerability is significant because attackers can circumvent existing application-level keyword blocklists - used to prevent common SQL injection patterns - by interleaving specific strings, such as 'master', into prohibited SQL keywords. This obfuscation technique enables the successful extraction of sensitive database contents. The Shadowserver Foundation first observed exploitation of this vulnerability on October 18, 2023. Given the ease of exploitation via simple HTTP GET requests and the potential for unauthorized data exfiltration, organizations utilizing ASP-CMS must prioritize remediation.

Attack Chain

1. Attacker performs reconnaissance to identify sites running ASP-CMS and target the commentList.asp script.
2. Attacker crafts a malicious HTTP GET request targeting the 'id' parameter.
3. Attacker uses SQL injection techniques, embedding obfuscated keywords (e.g., 'ma' + 'ster') to bypass internal blocklists.
4. The vulnerable commentList.asp endpoint processes the unsanitized 'id' parameter input.
5. The underlying database executes the injected SQL command.
6. Attacker observes application responses (or error messages) to confirm successful injection.
7. Attacker iterates requests to systematically dump table names, schemas, or sensitive records from the database.
8. Final objective is achieved: unauthorized exfiltration of sensitive database data.

Impact

Successful exploitation allows unauthenticated attackers to perform arbitrary database queries against an ASP-CMS installation. This can lead to the full compromise of database contents, including user credentials, administrative configurations, and application data. Historically, this has resulted in data exfiltration incidents observed globally since October 2023.

Recommendation

• Identify and audit all web servers hosting ASP-CMS for the presence of the vulnerable commentList.asp endpoint.
• Deploy the provided Sigma rule to web server access logs to detect potential SQL injection attempts targeting the id parameter.
• Patch or update the ASP-CMS installation to a version that implements proper parameter sanitization and parameterized queries.
• Apply a Web Application Firewall (WAF) rule to block requests where the 'id' parameter contains suspicious SQL patterns, specifically those attempting to bypass blocklists using obfuscation.