All Automation Controller NGINX web servers must have Web Distributed Authoring (WebDAV) disabled.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-256950	SRG-APP-000141-WSR-000085	APWS-AT-000340	SV-256950r960963_rule	2024-08-27	2

Description
Automation Controller NGINX web servers can be installed with functionality that, just by its nature, is not secure. Web Distributed Authoring (WebDAV) is an extension to the HTTP protocol that, when developed, was meant to allow users to create, change, and move documents on a server, typically a web server or web share. Allowing this functionality, development, and deployment is much easier for web authors. WebDAV is not widely used and has serious security concerns because it may allow clients to modify unauthorized files on the web server.

Description

Automation Controller NGINX web servers can be installed with functionality that, just by its nature, is not secure. Web Distributed Authoring (WebDAV) is an extension to the HTTP protocol that, when developed, was meant to allow users to create, change, and move documents on a server, typically a web server or web share. Allowing this functionality, development, and deployment is much easier for web authors. WebDAV is not widely used and has serious security concerns because it may allow clients to modify unauthorized files on the web server.

ℹ️ Check
As a system administrator, for each Automation Controller NGINX web server host, check the Automation Controller NGINX web server configuration for WebDAV modules: disallowed_modules=(nginx-dav-ext-module headers-more-nginx-module) ; echo "${disallowed_modules[]}" \| tr ' ' '\n' >tempfile ; nginx -V 2>&1 \| grep module \| tr ' ' '\n' \| grep module \| grep -v modules-path \| grep -Ff tempfile && echo "FAILED"; rm -f tempfile If "FAILED" is displayed, this is a finding. Check the Automation Controller NGINX web server configuration for WebDAV modules for disallowed WebDAV verbs, COPY, MOVE, MKCOL, PROPFIND, PROPPATCH, LOCK, UNLOCK: NGINXCONF=`nginx -V 2>&1 \| tr ' ' '\n' \| sed -ne '/conf-path/{s/.conf-path=\(.\)/\1/;p}' ` ; grep dev_(.)methods $NGINXCONF \| grep 'COPY\|MOVE\|MKCO\|PROPFIND\|PROPPATCH\|LOCK\|UNLOCK' && echo 'FAILED' If "FAILED" is displayed, this is a finding.

ℹ️ Check

As a system administrator, for each Automation Controller NGINX web server host, check the Automation Controller NGINX web server configuration for WebDAV modules: disallowed_modules=(nginx-dav-ext-module headers-more-nginx-module) ; echo "${disallowed_modules[*]}" | tr ' ' '\n' >tempfile ; nginx -V 2>&1 | grep module | tr ' ' '\n' | grep module | grep -v modules-path | grep -Ff tempfile && echo "FAILED"; rm -f tempfile If "FAILED" is displayed, this is a finding. Check the Automation Controller NGINX web server configuration for WebDAV modules for disallowed WebDAV verbs, COPY, MOVE, MKCOL, PROPFIND, PROPPATCH, LOCK, UNLOCK: NGINXCONF=`nginx -V 2>&1 | tr ' ' '\n' | sed -ne '/conf-path/{s/.*conf-path=$.*$/\1/;p}' ` ; grep dev_(.*)methods $NGINXCONF | grep 'COPY|MOVE|MKCO|PROPFIND|PROPPATCH|LOCK|UNLOCK' && echo 'FAILED' If "FAILED" is displayed, this is a finding.

✔️ Fix
As a system administrator, for each Automation Controller nginx web server host, remove all WebDAV modules from the NGINX configuration file (nominally /etc/nginx/nginx.conf). Reload the NGINX server configurations for all NGINX processes: $ pkill -HUP nginx