cis-tomcat8-v110-6-6

name	cis-tomcat8-v110-6.6
description	Control the maximum size of a POST request that will be parsed for parameters (Scored)
category	cis-tomcat
version	1.1.0
author	cyberstrike-official
tags	["cis","tomcat","tomcat-8","hardening","connector","post-size"]
cis_id	6.6
cis_benchmark	CIS Apache Tomcat 8 Benchmark v1.1.0
tech_stack	["linux","tomcat","java"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

6.6 Control the maximum size of a POST request that will be parsed for parameters (Scored)

Description

The maxPostSize attribute controls the maximum size of a POST request that will be parsed for parameters. Setting this to a reasonable value can help mitigate denial of service attacks that attempt to send large POST bodies.

Rationale

Limiting the size of POST requests that will be parsed for parameters helps prevent denial of service conditions where an attacker sends extremely large POST bodies to consume server resources.

Audit Procedure

Review the $CATALINA_HOME/conf/server.xml file. Ensure the maxPostSize attribute is set on each Connector:

$ grep -i maxPostSize $CATALINA_HOME/conf/server.xml

The maxPostSize should be set to a value appropriate for the applications hosted, typically 2097152 (2MB) or less.

Remediation

In the $CATALINA_HOME/conf/server.xml file, add the maxPostSize attribute to each Connector element:

<Connector ... maxPostSize="2097152" />

Default Value

The default value is 2097152 (2MB) in Tomcat 8.

References

1. https://tomcat.apache.org/tomcat-8.0-doc/config/http.html

CIS Controls

v7:

• 9.4 Apply Host-based Firewalls or Port Filtering
  • Apply host-based firewalls or port filtering tools on end systems, with a default-deny rule that drops all traffic except those services and ports that are explicitly allowed.

Profile Applicability

• Level 1