Samba: Execution of arbitrary code

Background

Samba is a suite of SMB and CIFS client/server programs for UNIX.

Description

Alin Rad Pop (Secunia Research) discovered a boundary checking error in the send_mailslot() function which could lead to a stack-based buffer overflow.

Impact

A remote attacker could send a specially crafted “SAMLOGON” domain logon packet, possibly leading to the execution of arbitrary code with elevated privileges. Note that this vulnerability is exploitable only when domain logon support is enabled in Samba, which is not the case in Gentoo’s default configuration.

Workaround

Disable domain logon in Samba by setting “domain logons = no” in the “global” section of your smb.conf and restart Samba.

Resolution

All Samba users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-fs/samba-3.0.28"