SMB1/2/3 connections may not require signing where they should

ID SAMBA:CVE-2017-12150
Type samba
Reporter Samba
Modified 2017-09-20T00:00:00


There are several code paths where the code doesn't enforce SMB signing: The fixes for CVE-2015-5296 didn't apply the implied signing protection when enforcing encryption for commands like 'smb2mount -e', 'smbcacls -e' and 'smbcquotas -e'. The python binding exported as 'samba.samba3.libsmb_samba_internal' doesn't make use of the "client signing" smb.conf option. libgpo as well as 'net ads gpo' doesn't require SMB signing when fetching group policies. Commandline tools like 'smbclient', 'smbcacls' and 'smbcquotas' allow a fallback to an anonymous connection when using the '--use-ccache' option and this happens even if SMB signing is required.