[ GLSA 200711-29 ] Samba: Execution of arbitrary code

[GLSA]

Gentoo Linux Security Advisory

Title: Samba: Execution of arbitrary code (GLSA 200711-29)
Severity: high
Exploitable: remote
Date: November 20, 2007
Updated: December 05, 2007
Bug(s): #197519
ID: 200711-29

Synopsis


Samba contains two buffer overflow vulnerabilities potentially resulting in
the execution of arbitrary code.


Background


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


Affected Packages

Package: net-fs/samba
Vulnerable: < 3.0.27a
Unaffected: >= 3.0.27a
Architectures: All supported architectures


Description


Two vulnerabilities have been reported in nmbd. Alin Rad Pop (Secunia
Research) discovered a boundary checking error in the
reply_netbios_packet() function which could lead to a stack-based
buffer overflow (CVE-2007-5398). The Samba developers discovered a
boundary error when processing GETDC logon requests also leading to a
buffer overflow (CVE-2007-4572).


Impact


To exploit the first vulnerability, a remote unauthenticated attacker
could send specially crafted WINS "Name Registration" requests followed
by a WINS "Name Query" request. This might lead to execution of
arbitrary code with elevated privileges. Note that this vulnerability
is exploitable only when WINS server support is enabled in Samba. The
second vulnerability could be exploited by sending specially crafted
"GETDC" mailslot requests, but requires Samba to be configured as a
Primary or Backup Domain Controller. It is not believed the be
exploitable to execute arbitrary code.


Workaround


To work around the first vulnerability, disable WINS support in Samba
by setting " wins support = no " in the "global" section of your
smb.conf and restart Samba.


Resolution


All Samba users should upgrade to the latest version: