Security Bulletin: Vulnerability in Diffie-Hellman ciphers affects IBM Flex System Manager (FSM) SMIA Configuration Tool (CVE-2015-4000)

Vulnerability Details

Summary

The Logjam Attack on TLS connections using the Diffie-Hellman (DH) key exchange protocol affects IBM Flex System Manager (FSM) SMIA Configuration Tool (also known as Network Advisor).

Vulnerability Details:

CVE-ID: CVE-2015-4000

Description: The TLS protocol could allow a remote attacker to obtain sensitive information, caused by the failure to properly convey a DHE_EXPORT ciphersuite choice. An attacker could exploit this vulnerability using man-in-the-middle techniques to force a downgrade to 512-bit export-grade cipher. Successful exploitation could allow an attacker to recover the session key as well as modify the contents of the traffic. This vulnerability is commonly referred to as "Logjam".

CVSS Base Score: 4.3
CVSS Temporal Score: See http://exchange.xforce.ibmcloud.com/vulnerabilities/103294 for current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:M/Au:N/C:P/I:N/A:N)

Affected products and versions

• Flex System Manager 1.1.x.x
• Flex System Manager 1.2.0.x
• Flex System Manager 1.2.1.x
• Flex System Manager 1.3.0.x
• Flex System Manager 1.3.1.x
• Flex System Manager 1.3.2.x
• Flex System Manager 1.3.3.x

Remediation/Fixes:

You should verify applying this configuration change does not cause any compatibility issues. If you change the default setting after applying the fix, you will expose yourself to the attack described above. IBM recommends that you review your entire environment to identify other areas where you have enabled the Diffie-Hellman key-exchange protocol used in TLS and take appropriate mitigation and remediation actions.

Workarounds and Mitigations:

None

References:

• Complete CVSS Guide
• On-line Calculator V2

Related Information:
IBM Secure Engineering Web Portal
IBM Product Security Incident Response Blog

Acknowledgement

None

Change History
26 June 2015: Original Copy Published
29 July 2015: Updated APAR and SMIA Remediation locations

* The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.

Disclaimer

According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.