Ensure scheme is set accurately

MediumLevel 1Automatedtomcat

Description

The scheme attribute is used to indicate to callers of request.getScheme() which scheme is in use by the Connector. Ensure the scheme attribute is set to http for Connectors operating over HTTP. Ensure the scheme attribute is set to https for Connectors operating over HTTPS. For every Connector: SSLEnabled="true" requires scheme="https"; other connectors must have scheme unset or "http". Reads $CATALINA_BASE (default /opt/tomcat) and $CATALINA_HOME (default: $CATALINA_BASE); set them for packaged installs (e.g. CATALINA_BASE=/var/lib/tomcat10, CATALINA_HOME=/usr/share/tomcat10). XML comments are ignored.

How it is checked

Audit method: Shell command

shell

B=${CATALINA_BASE:-/opt/tomcat}; H=${CATALINA_HOME:-$B}; O=${TOMCAT_OWNER:-tomcat_admin}; G=${TOMCAT_GROUP:-tomcat}; x(){ [ -r "$1" ] || return 1; awk 'BEGIN{RS="<!--"} NR==1{print;next} {i=index($0,"-->"); if(i) print substr($0,i+3)}' "$1" | tr '\n\t\r' '   ' | tr '<' '\n'; }; s=$(x "$B/conf/server.xml") || exit 1; printf '%s\n' "$s" | awk 'function at(n,  r){if(match($0,"[[:space:]]" n "[[:space:]]*=[[:space:]]*[\"\047][^\"\047]*")){r=substr($0,RSTART,RLENGTH); sub(/^[^=]*=[[:space:]]*./,"",r); return r} return "-unset-"} function fin(){ if(!inc) return; inc=0; if(se){ if(sc!="https") bad=1 } else if(sc!="-unset-" && sc!="http") bad=1; } /^Connector[[:space:]]/{fin(); inc=1; se=(at("SSLEnabled")=="true"); sc=at("scheme"); sx=at("secure"); pr=at("sslProtocol"); if(pr=="-unset-") pr=""; if($0~/\/>[[:space:]]*$/) fin(); next} /^SSLHostConfig[[:space:]]/ && inc {v=at("sslProtocol"); if(v=="-unset-") v=at("protocols"); if(v!="-unset-") pr=pr "," v} /^\/Connector>/{fin()} END{fin(); print bad?"noncompliant":"compliant"}'

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Set scheme="https" on TLS connectors and scheme="http" (or none) on plain HTTP connectors in server.xml. Restart Tomcat afterwards.

Properties

Operating systems: Any
Tags: tomcattls
Reference: CIS Apache Tomcat 10.1 Benchmark v1.0.0 - 6.3 Ensure scheme is set accurately

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target tomcat