Rise in SQL injection attacks exploiting unverified user data input
Microsoft is aware of a recent escalation in a class of attacks targeting Web sites that use Microsoft ASP and ASP.NET technologies but do not follow best practices for secure Web application development. These SQL injection attacks do not exploit a specific software vulnerability, but instead target Web sites that do not follow secure coding practices for accessing and manipulating data stored in a relational database. When a SQL injection attack succeeds, an attacker can compromise data stored in these databases and possibly execute remote code. Clients browsing to a compromised server could be forwarded unknowingly to malicious sites that may install malware on the client machine.
This vulnerability is not exploitable in Web applications that follow generally accepted best practices for secure Web application development by verifying user data input.
Microsoft has identified several tools to assist administrators. These tools cover detection, defense, and identifying possible coding which may be exploited by an attacker.
- Detection – HP Scrawlr – Hewlett Packard has developed a free scanner which can identify whether sites are susceptible to SQL injection. This tool and support for its use can be found at Finding SQL Injection with Scrawlr.
- Defense – UrlScan version 3.0 Beta – UrlScan version 3.0 Beta is a Microsoft security tool that restricts the types of HTTP requests that Internet Information Services (IIS) will process. By blocking specific HTTP requests, UrlScan helps prevent potentially harmful requests from reaching the Web application on the server. UrlScan 3.0 will install on IIS 5.1 and later, including IIS 7.0. UrlScan 3.0 can be found here.
- Identifying – Microsoft Source Code Analyzer for SQL Injection – A SQL Source Code Analysis Tool has been developed. This tool can be used to detect ASP code susceptible to SQL injection attacks. This tool can be found here.