Security Bulletin: Vulnerability in RC4 stream cipher affects Algo Credit Limits (CVE-2015-2808)

Summary

The RC4 “Bar Mitzvah” Attack for SSL/TLS affects Algo Credit Limits.

Vulnerability Details

CVEID: CVE-2015-2808 DESCRIPTION: The RC4 algorithm, as used in the TLS protocol and SSL protocol, could allow a remote attacker to obtain sensitive information. An attacker could exploit this vulnerability to remotely expose account credentials without requiring an active man-in-the-middle session. Successful exploitation could allow an attacker to retrieve credit card data or other sensitive information. This vulnerability is commonly referred to as “Bar Mitzvah Attack”.
CVSS Base Score: 5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/101851 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:P/I:N/A:N)

Affected Products and Versions

Algo Credit Limits 4.7 and earlier

Remediation/Fixes

A fix has been created for version 4.5.0.05 and 4.7.0.03 of the named product. Download and install the fix as soon as practicable. Fix and installation instructions are provided at the URL listed below.

For versions prior to 4.7.0 IBM recommends upgrading to a fixed, supported version/release/platform of the product.

As the length of the server key size are increased, the amount of CPU required for full TLS/SSL handshake can significantly increase. Please carefully test and assess the impact to your CPU requirements to ensure sufficient CPU resources, otherwise the system availability may be impacted.

You should verify applying this configuration change does not cause any compatibility issues. Not disabling the RC4 stream cipher 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 RC4 stream cipher and take appropriate mitigation and remediation actions.

Workarounds and Mitigations

To disable the RC4 stream cipher in your Algo Credit Limits server installation,****edit $ACLM_HOME/jlib/platform/jre/jre/lib/security/java.security. Find the linejdk.tls.disabledAlgorithms=SSLv3 and change it tojdk.tls.disabledAlgorithms=SSLv3,RC4

You should verify applying this configuration change does not cause any compatibility issues. Not disabling the RC4 stream cipher 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 RC4 stream cipher and take appropriate mitigation and remediation actions.