CVE-2016-2124

Related Vulnerabilities: CVE-2016-2124  

A flaw was found in the way samba implemented SMB1 authentication. An attacker could use this flaw to retrieve the plaintext password sent over the wire even if Kerberos authentication was required.

Description

A flaw was found in the way samba implemented SMB1 authentication. An attacker could use this flaw to retrieve the plaintext password sent over the wire even if Kerberos authentication was required.

Mitigation

Ensure the following [global] smb.conf parameters are set to their default values as shown below:

  client lanman auth = no
client NTLMv2 auth = yes
client plaintext auth = no
client min protocol = SMB2_02

Or use the '-k' command line option only without the -U option, which will make use of an existing krb5 ccache.

Additional Information

  • Bugzilla 2019660: CVE-2016-2124 samba: SMB1 client connections can be downgraded to plaintext authentication
  • CWE-287: Improper Authentication
  • FAQ: Frequently asked questions about CVE-2016-2124