The Security Token Service must use the "setCharacterEncodingFilter" filter.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-239672	VCST-67-000021	SV-239672r816741_rule		Medium

Description
Invalid user input occurs when a user inserts data or characters into a hosted application's data entry field and the hosted application is unprepared to process that data. This results in unanticipated application behavior, potentially leading to an application compromise. Invalid user input is one of the primary methods employed when attempting to compromise an application. An attacker can also enter Unicode characters into hosted applications in an effort to break out of the document home or root home directory or to bypass security checks. VMware uses the standard Tomcat "SetCharacterEncodingFilter" to provide a layer of defense against character encoding attacks. Filters are Java objects that perform filtering tasks on the request to a resource (a servlet or static content), the response from a resource, or both.

Description

Invalid user input occurs when a user inserts data or characters into a hosted application's data entry field and the hosted application is unprepared to process that data. This results in unanticipated application behavior, potentially leading to an application compromise. Invalid user input is one of the primary methods employed when attempting to compromise an application. An attacker can also enter Unicode characters into hosted applications in an effort to break out of the document home or root home directory or to bypass security checks. VMware uses the standard Tomcat "SetCharacterEncodingFilter" to provide a layer of defense against character encoding attacks. Filters are Java objects that perform filtering tasks on the request to a resource (a servlet or static content), the response from a resource, or both.

STIG	Date
VMware vSphere 6.7 STS Tomcat Security Technical Implementation Guide	2022-01-03

Details

Check Text ( C-42905r816739_chk )
Connect to the PSC, whether external or embedded. At the command prompt, execute the following command: # xmllint --format /usr/lib/vmware-sso/vmware-sts/conf/web.xml \| sed '2 s/xmlns="."//g' \| xmllint --xpath '/web-app/filter-mapping/filter-name[text()="setCharacterEncodingFilter"]/parent::filter-mapping' - Expected result: setCharacterEncodingFilter / If the output is does not match the expected result, this is a finding. At the command prompt, execute the following command: # xmllint --format /usr/lib/vmware-sso/vmware-sts/conf/web.xml \| sed '2 s/xmlns=".*"//g' \| xmllint --xpath '/web-app/filter/filter-name[text()="setCharacterEncodingFilter"]/parent::filter' - Expected result: setCharacterEncodingFilter org.apache.catalina.filters.SetCharacterEncodingFilter encoding UTF-8 ignore true true If the output is does not match the expected result, this is a finding.

Check Text ( C-42905r816739_chk )

Connect to the PSC, whether external or embedded.

At the command prompt, execute the following command:

# xmllint --format /usr/lib/vmware-sso/vmware-sts/conf/web.xml | sed '2 s/xmlns=".*"//g' | xmllint --xpath '/web-app/filter-mapping/filter-name[text()="setCharacterEncodingFilter"]/parent::filter-mapping' -

Expected result:

setCharacterEncodingFilter

If the output is does not match the expected result, this is a finding.

At the command prompt, execute the following command:

# xmllint --format /usr/lib/vmware-sso/vmware-sts/conf/web.xml | sed '2 s/xmlns=".*"//g' | xmllint --xpath '/web-app/filter/filter-name[text()="setCharacterEncodingFilter"]/parent::filter' -

Expected result:

setCharacterEncodingFilter

org.apache.catalina.filters.SetCharacterEncodingFilter

encoding

UTF-8

ignore

true

If the output is does not match the expected result, this is a finding.

Fix Text (F-42864r816740_fix)
Connect to the PSC, whether external or embedded. Navigate to and open /usr/lib/vmware-sso/vmware-sts/conf/web.xml. Configure the node with the child nodes listed below: setCharacterEncodingFilter /* setCharacterEncodingFilter org.apache.catalina.filters.SetCharacterEncodingFilter encoding UTF-8 ignore true true