Security Bulletin: Vulnerability in MD5 Signature and Hash Algorithm affects IBM Flex System FC5022 16Gb SAN Scalable Switch (CVE-2015-7575)

Summary

The MD5 “SLOTH” vulnerability on TLS 1.2 affects IBM Flex System FC5022 16Gb SAN Scalable Switch.

Vulnerability Details

Summary

The MD5 “SLOTH” vulnerability on TLS 1.2 affects IBM Flex System FC5022 16Gb SAN Scalable Switch.

Vulnerability Details:

CVE-ID: CVE-2015-7575

Description: The TLS protocol could allow weaker than expected security caused by a collision attack when using the MD5 hash function for signing a ServerKeyExchange message during a TLS handshake. An attacker could exploit this vulnerability using man-in-the-middle techniques to impersonate a TLS server and obtain credentials.

CVSS Base Score: 7.1
CVSS Temporal Score: See <http://exchange.xforce.ibmcloud.com/vulnerabilities/109415&gt; for current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N)

Affected Products and Versions

Remediation/Fixes:

Firmware fix versions are available on Fix Central:
<http://www.ibm.com/support/fixcentral/&gt;.

You should verify applying this fix does not cause any compatibility issues. The fix disables MD5 signature hash by default. 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 MD5 signature hash and take appropriate mitigation and remediation actions.

Workaround(s) & Mitigation(s):

None

References:

• Complete CVSS v3 Guide
• On-line Calculator v3

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

Acknowledgement

Reported to IBM by Karthikeyan Bhargavan at INRIA in Paris, France.

Change History
06 July 2016: Original Copy Published

• 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.