Ensure actions as another user are always logged

BajaNivel 2Automatizadalinux

Descripción

sudo provides users with temporary elevated privileges to perform operations, either as the superuser or another user.

Cómo se verifica

Método de auditoría: Comando de shell

shell

alt0() { o=$(bash -c 'awk '"'"'/^ *-a *always,exit/ &&/ -F *arch=b(32|64)/ &&(/ -F *auid!=unset/||/ -F *auid!=-1/||/ -F *auid!=4294967295/) &&(/ -C *euid!=uid/||/ -C *uid!=euid/) &&/ -S *execve/ &&(/ key= *[!-~]* *$/||/ -k *[!-~]* *$/)'"'"' /etc/audit/rules.d/*.rules' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-a always,exit -F arch=b64 -C euid!=uid -F auid!=unset -S execve -k user_emulation' || { echo step1: missing '-a always,exit -F arch=b64 -C euid!=uid -F auid!=unset -S ex'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-a always,exit -F arch=b32 -C euid!=uid -F auid!=unset -S execve -k user_emulation' || { echo step1: missing '-a always,exit -F arch=b32 -C euid!=uid -F auid!=unset -S ex'; return 1; }; o=$(bash -c 'auditctl -l | awk '"'"'/^ *-a *always,exit/ &&/ -F *arch=b(32|64)/ &&(/ -F *auid!=unset/||/ -F *auid!=-1/||/ -F *auid!=4294967295/) &&(/ -C *euid!=uid/||/ -C *uid!=euid/) &&/ -S *execve/ &&(/ key= *[!-~]* *$/||/ -k *[!-~]* *$/)'"'"'' 2>&1); printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-a always,exit -F arch=b64 -S execve -C uid!=euid -F auid!=-1 -F key=user_emulation' || { echo step2: missing '-a always,exit -F arch=b64 -S execve -C uid!=euid -F auid!=-'; return 1; }; printf '%s\n' "$o" | tr -s ' \t' '  ' | sed 's/^ //;s/ $//' | grep -Fxq -- '-a always,exit -F arch=b32 -S execve -C uid!=euid -F auid!=-1 -F key=user_emulation' || { echo step2: missing '-a always,exit -F arch=b32 -S execve -C uid!=euid -F auid!=-'; return 1; }; }; if alt0; then echo compliant; fi

Salida esperada: compliant

Cómo se corrige

Método de corrección: Guía o parche de infraestructura

Create audit rules Edit or create a file in the /etc/audit/rules.d/ directory, ending in .rules extension, with the relevant rules to monitor elevated privileges. Example: # printf " -a always,exit -F arch=b64 -C euid!=uid -F auid!=unset -S execve -k user_emulation -a always,exit -F arch=b32 -C euid!=uid -F auid!=unset -S execve -k user_emulation " >> /etc/audit/rules.d/50-user_emulation.rules Load audit rules Merge and load the rules into active configuration: # augenrules --load Check if reboot is required. # if [[ $(auditctl -s | grep "enabled") =~ "2" ]]; then printf "Reboot required to load rules\n"; fi

Propiedades

Sistemas operativos: ubuntu-20.04
Etiquetas: cis-convertedlinux
Referencia: CIS Ubuntu Linux 20.04 LTS Benchmark v3.0.0 - 6.3.3.2

Verificar este host

Ejecute esto en un equipo que tenga permiso para auditar. El escaneo es de solo lectura.

shell

tmaegis scan --target linux --level 2