Ensure the LimitRequestLine directive is Set to 8190 or less but not 0

LowLevel 2Automatedapache

Description

Buffer Overflow attacks attempt to exploit an application by providing more data than the application buffer can contain. If the application allows copying data to the buffer to overflow the boundaries of the buffer, then the application is vulnerable to a buffer overflow. LimitRequestLine must be set and every value must be 1-8190. Reads the main configuration (APACHE_CONF overrides; default /etc/apache2/apache2.conf, /etc/httpd/conf/httpd.conf or /usr/local/apache2/conf/httpd.conf) and every Include/IncludeOptional file.

How it is checked

Audit method: Shell command

shell

c=${APACHE_CONF:-}; if [ -z "$c" ]; then for f in /etc/apache2/apache2.conf /etc/httpd/conf/httpd.conf /usr/local/apache2/conf/httpd.conf /etc/apache2/httpd.conf; do [ -f "$f" ] && { c=$f; break; }; done; fi; [ -r "$c" ] || exit 1; R=$(awk 'tolower($1)=="serverroot"{v=$2; gsub(/"/,"",v); print v; exit}' "$c"); [ -n "$R" ] || R=$(dirname "$c"); shopt -s nocasematch; inc(){ local p g l; [ ${#FUNCNAME[@]} -lt 16 ] || return 0; p=$1; case $p in /*) ;; *) p=$R/$p;; esac; [ -d "$p" ] && p="$p/*"; for g in $p; do [ -f "$g" ] || continue; while IFS= read -r l || [ -n "$l" ]; do if [[ $l =~ ^[[:space:]]*include(optional)?[[:space:]]+\"?([^\"[:space:]]+) ]]; then inc "${BASH_REMATCH[2]}"; else printf '%s\n' "$l"; fi; done < "$g"; done; }; cfg=$(inc "$c" | sed -e 's/^[[:space:]]*//' -e '/^#/d' -e '/^$/d'); shopt -u nocasematch; printf '%s\n' "$cfg" | awk 'tolower($1)=="limitrequestline"{n++; v=$2+0; if(!(v>=1 && v<=8190)) bad=1} END{print (n>0&&!bad)?"compliant":"noncompliant"}'

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Set LimitRequestLine 8190 (or lower, not 0). Then run apachectl configtest and reload Apache.

Properties

Operating systems: Any
Tags: apacherequest-limits
Reference: CIS Apache HTTP Server 2.4 Benchmark v2.4.0 - 10.1 Ensure the LimitRequestLine directive is Set to 8190 or less but not 0

Check this host

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

shell

tmaegis scan --target apache --level 2