Privilege escalation can occur in the SUSE useradd.c code in useradd, as distributed in the SUSE shadow package through 4.2.1-27.9.1 for SUSE Linux Enterprise 12 (SLE-12) and through 4.5-5.39 for SUSE Linux Enterprise 15 (SLE-15). Non-existing intermediate directories are created with mode 0777 during user creation. Given that they are world-writable, local attackers might use this for privilege escalation and other unspecified attacks. NOTE: this would affect non-SUSE users who took useradd.c code from a 2014-04-02 upstream pull request; however, no non-SUSE distribution is known to be affected.
http://lists.opensuse.org/opensuse-security-announce/2018-09/msg00073.html