TMA-KERBEROS-KEYTAB-PERMS

Ensure keytab files are owned by root and accessible only by their owner

ÉlevéeNiveau 1Automatiséekerberos

Description

Keytabs contain long-term service keys usable to impersonate the service or decrypt its tickets. Checks /etc/krb5.keytab and the kadmind keytab (/etc/krb5kdc/kadm5.keytab or /var/kerberos/krb5kdc/kadm5.keytab): each existing file must be owned by root with no group or other permissions.

Méthode de vérification

Méthode d'audit: Commande shell

shell

n=0; bad=0
for f in /etc/krb5.keytab /etc/krb5kdc/kadm5.keytab /var/kerberos/krb5kdc/kadm5.keytab; do
  [ -f "$f" ] || continue
  n=$((n+1))
  o=$(stat -Lc %U "$f") || exit 1
  [ "$o" = root ] || { echo "$f owned by $o"; bad=1; }
  [ -z "$(find -L "$f" -maxdepth 0 -perm /077)" ] || { echo "$f is accessible by group/other"; bad=1; }
done
[ "$n" -gt 0 ] && [ "$bad" -eq 0 ] && echo compliant

Sortie attendue: compliant

Méthode de correction

Méthode de correction: Recommandation ou correctif d'infrastructure

chown root:root <keytab> && chmod 600 <keytab> for each keytab listed. If a non-root service must read a keytab, give it a dedicated per-service keytab (ktutil) owned by that service account with mode 600 instead of opening /etc/krb5.keytab.

Propriétés

Systèmes d'exploitation: Tous
Étiquettes: kerberospermissionskeys
Référence: CIS MIT Kerberos / Linux Benchmark guidance - Keytab file permissions (verify section number for your release)

Vérifier cet hôte

Exécutez cette commande sur une machine que vous êtes autorisé à auditer. L'analyse est en lecture seule.

shell

tmaegis scan --target kerberos