SAMBA RPC Memory Corruption and Code Execution

Notification Type: IBM Security Protection Alert
Notification Date: April 20, 2012
Notification Version: 1.0
   
Name: SAMBA RPC Memory Corruption and Code Execution
Public disclosure/
In the wild date:
April 10, 2012
Risk: Critical
CVE: CVE-2012-1182
Description: Samba could allow a remote attacker to execute arbitrary code on the system, caused by an error within the Network Data Representation (NDR) marshalling functionality. An attacker could exploit this vulnerability using a specially-crafted RPC call to execute arbitrary code on the system with root privileges.

 

ISS Coverage

Product Content Version
Proventia Network IDS
Proventia Network IPS
Proventia Network MFS
Proventia Server (Linux)
RealSecure Network
RealSecure Server Sensor
32.041
Proventia Desktop
Proventia Server IPS (Windows)
2755
Propagation Techniques ISS Protection Available

remote exploit

SMB_Samba_PIDL_Overflow*
 20 Apr 2012

* This signature is NOT blocked by default. X-Force recommends that this signature be enabled for monitoring and set to block only after evaluating in your environment.

 

Detailed Description

Business Impact:

This security update resolves a privately disclosed vulnerability in SAMBA's RPC communications. The vulnerability could allow remote code execution if a network perimeter permits SMB traffic to get inside.

*CVSS Base Score: 10
  Access Vector: Network
Access Complexity: Low
Authentication: None
Confidentiality Impact: Complete
Integrity Impact: Complete
Availability Impact: Complete
Adjusted Temporal Score: 7.4
  Exploitability: Unproven
Remediation Level: Official-Fix
Report Confidence: Confirmed
Affected Products: For a full list of affected versions, see references below.
Technical Description:

SAMBA version 3.6.3 and previous contain a vulnerability that can be exploited to gain remote code execution in the context of the "root" user.  Unless SAMBA is specifically configured to restrict users via the "hosts allow" parameter, this attack can be performed without authentication.  The code handling the interface definition language (IDL) for Microsoft's remote procedure call (MSRPC) incorrectly validates input regarding arrays which allows for user controlled data to be written past a heap buffer.  Proof of concept code triggering this vulnerability is publicly available and proof of concept code to gain Remote Code Execution out of SAMBA heap overflows is also available, so this should be patched immediately.

Remediation: A patch is available, see references below for details.

References

XFDB: http://xforce.iss.net/xforce/xfdb/74721
Samba: http://www.samba.org

Revision History

1.0 Initial publication.

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