cis-tomcat101-2-1

name	cis-tomcat101-2.1
description	Alter the Advertised server.info String (Manual)
category	cis-tomcat
version	1.0.0
author	cyberstrike-official
tags	["cis","tomcat","linux","java","information-leakage","server-info"]
cis_id	2.1
cis_benchmark	CIS Apache Tomcat 10.1 Benchmark v1.0.0
tech_stack	["linux","tomcat","java"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

Alter the Advertised server.info String (Manual)

Description

The server.info attribute contains the name of the application service. This value is presented to Tomcat clients when clients connect to the tomcat server.

Rationale

Altering the server.info attribute may increase the complexity for attackers to determine which vulnerabilities affect the server platform.

Audit Procedure

Perform the following to determine if the server.info value has been changed: Extract the ServerInfo.properties file and examine the server.info attribute.

$ cd $CATALINA_HOME/lib
$ jar xf catalina.jar org/apache/catalina/util/ServerInfo.properties
$ grep server.info org/apache/catalina/util/ServerInfo.properties

Remediation

Perform the following to alter the server platform string that gets displayed when clients connect to the tomcat server.

1. Extract the ServerInfo.properties file from the catalina.jar file:

$ cd $CATALINA_HOME/lib
$ jar xf catalina.jar org/apache/catalina/util/ServerInfo.properties

2. Navigate to the util directory that was created

cd org/apache/catalina/util

3. Open ServerInfo.properties in an editor
4. Update the server.info attribute in the ServerInfo.properties file.

server.info=<SomeWebServer>

5. Update the catalina.jar with the modified ServerInfo.properties file.

$ jar uf catalina.jar org/apache/catalina/util/ServerInfo.properties

Default Value

The default value for the server.info attribute is Apache Tomcat/. For example, Apache Tomcat/9.0.0.M9.

References

1. https://www.owasp.org/index.php/Securing_tomcat

CIS Controls

v8:

• 16.7 Use Standard Hardening Configuration Templates for Application Infrastructure
  • Use standard, industry-recommended hardening configuration templates for application infrastructure components. This includes underlying servers, databases, and web servers, and applies to cloud containers, Platform as a Service (PaaS) components, and SaaS components. Do not allow in-house developed software to weaken configuration hardening.