Linux distributions
TMA-RHEL10-1.6.4
Ensure system wide crypto policy disables cbc for ssh
Descripción
Cypher Block Chaining (CBC) is an algorithm that uses a block cipher.
Cómo se verifica
Método de auditoría: Comando de shell
alt0() { command -v grep >/dev/null 2>&1 || { echo "step1: grep not installed"; return 1; }; o=$(bash -c 'grep -Pi -- '"'"'^\h*cipher\h*=\h*([^#\n\r]+)?-CBC\b'"'"' /etc/crypto-' 2>&1); printf '%s\n' "$o" | tr -s ' \t' ' ' | sed 's/^ //;s/ $//' | grep -Fxq -- policies/state/CURRENT.pol || { echo step1: missing policies/state/CURRENT.pol; return 1; }; o=$(bash -c 'grep -Pi -- '"'"'^\h*cipher@(lib|open)ssh(-server|-client)?\h*=\h*([^#\n\r]+)?- CBC\b'"'"' /etc/crypto-policies/state/CURRENT.pol' 2>/dev/null); [ -z "$o" ] || { echo "step2: $o" | head -c 300; return 1; }; }; if alt0; then echo compliant; fi- Salida esperada
compliant
Cómo se corrige
Método de corrección: Guía o parche de infraestructura
Note: • The commands below are written for the included DEFAULT system-wide crypto policy. If another policy is in use and follows local site policy, replace DEFAULT with the name of your system-wide crypto policy. • CBC can be turned off globally by using the argument cipher opposed to cipher@SSH • Multiple subpolicies may be assigned to a policy as a colon separated list. e.g. DEFAULT:NO-SHA1:NO-SSHCBC • Subpolicies: o Not included in the update-crypto-policies --set command will not be applied to the system wide crypto policy. o must exist before they can be applied to the system wide crypto policy. o .pmod file filenames must be in all upper case, upper case, e.g. NO- SSHCBC.pmod, or the…
Propiedades
- Sistemas operativos
- rhel-10
- Etiquetas
- cis-convertedlinux
- Referencia
- CIS Red Hat Enterprise Linux 10 Benchmark v1.0.1 - 1.6.4
Verificar este host
Ejecute esto en un equipo que tenga permiso para auditar. El escaneo es de solo lectura.
tmaegis scan --target linux