Security Bulletin: Vulnerability in Diffie-Hellman ciphers affects Rational Directory Server (CVE-2015-4000)

Summary

The Logjam Attack on TLS connections using the Diffie-Hellman (DH) key exchange protocol affects Rational Directory Server.

Vulnerability Details

CVEID: 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 https://exchange.xforce.ibmcloud.com/vulnerabilities/103294 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:M/Au:N/C:P/I:N/A:N)

Affected Products and Versions

Product

| Version
—|—
Rational Directory Server (Tivoli) | 5.2 - 5.2.1_iFix007
Rational Directory Server (Apache)| 5.1.1 - 5.1.1.2_iFix008

Remediation/Fixes

Product

| Download link
—|—
IBM Rational Directory Server 5.2 (Tivoli) and above| RDS_5.2.1_iFix08
IBM Rational Directory Server 5.1.1 (Apache) and above| RDS_5.1.1.2_iFix09

Workarounds and Mitigations

None