Ensure TCP SYN Cookies is enabled

SrednjaNivo 1Automatskabottlerocket

Opis

When tcp_syncookies is set, the kernel will handle TCP SYN packets normally until the half-open connection queue is full, at which time, the SYN cookie functionality kicks in. SYN cookies work by not using the SYN queue at all. The audit reads the running value from /proc/sys. Run tmaegis on the host through the admin container root shell (sudo sheltie).

Kako se proverava

Metod provere: Komanda ljuske

shell

bad=0
chk() { f=/proc/sys/$(printf %s "$1" | tr . /); v=$(cat "$f" 2>/dev/null) || { echo "$1: not readable"; bad=1; return; }; [ "$v" = "$2" ] || { echo "$1 = $v (expected $2)"; bad=1; }; }
chk net.ipv4.tcp_syncookies 1
[ "$bad" -eq 0 ] && echo compliant

Očekivani izlaz: compliant

Kako se ispravlja

Metod ispravke: Smernica ili zakrpa infrastrukture

Run the following command to set the active kernel parameter and persist the setting: # apiclient apply <<EOF [settings.kernel.sysctl] "net.ipv4.tcp_syncookies" = "1" EOF Run the following command to flush the routing cache: # sysctl -w net.ipv4.route.flush=1

Svojstva

Operativni sistemi: Bilo koji
Oznake: bottlerocketnetwork
Referenca: CIS Bottlerocket Benchmark v1.0.0 - 3.2.7 Ensure TCP SYN Cookies is enabled

Proverite ovaj računar

Pokrenite ovo na računaru za koji imate dozvolu za proveru. Skeniranje radi u režimu samo za čitanje.

shell

tmaegis scan --target bottlerocket