ABSTRACT

An invalid servlet name can prevent legitimate access to the intended Servlet.

EXPLANATION

A missing or duplicate servlet name in web.xml is an error. Every Servlet should have a unique name (servlet-name) and a corresponding mapping (servlet-mapping).



Example 1: The following entry from web.xml shows several erroneous servlet definitions.


<!-- No <servlet-name> specified: -->
<servlet>
<servlet-class>com.class.MyServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>

<!-- Empty <servlet-name> node: -->
<servlet>
<servlet-name/>
<servlet-class>com.class.MyServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>

<!-- Duplicate <servlet-name> nodes: -->
<servlet>
<servlet-name>MyServlet</servlet-name>
<servlet-name>Servlet</servlet-name>
<servlet-class>com.class.MyServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>

These errors may cause an unintentional denial of access to the Servlet.

REFERENCES

[1] Standards Mapping - OWASP Top 10 2004 - (OWASP 2004) A9 Application Denial of Service

[2] Standards Mapping - Security Technical Implementation Guide Version 3 - (STIG 3) APP6080 CAT II

[3] Standards Mapping - Common Weakness Enumeration - (CWE) CWE ID 730

[4] Sun Microsystems, Inc. Java Servlet Specification 2.4

[5] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 - (PCI 1.1) Requirement 6.5.9