Security Bulletin
Summary
OpenSSL vulnerabilities were disclosed by the OpenSSL Project and affect Rational Application Developer for WebSphere Software. This includes the Logjam Attack on TLS connections using the Diffie-Hellman (DH) key exchange protocol (CVE-2015-4000). This also includes the alternate chains certificate forgery vulnerability (CVE-2015-1793). Rational Application Developer for WebSphere Software has addressed the applicable CVEs.
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)
CVEID: CVE-2015-1793
DESCRIPTION: OpenSSL could allow a remote attacker to bypass security restrictions, caused by an implementation error of the alternative certificate chain logic. An attacker could exploit this vulnerability to bypass the CA flag and other specific checks on untrusted certificates and issue an invalid certificate.
CVSS Base Score: 7.5
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/104500 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N)
Affected Products and Versions
IBM Rational Application Developer for WebSphere Software 9.1, 9.1.0.1, and 9.1.1
Remediation/Fixes
Update the IBM SDK for Node.js using by the Cordova platform in the product to address this vulnerability:
| Product | VRMF | APAR | Remediation/First Fix |
| Rational Application Developer | 9.1, 9.1.0.1, and 9.1.1 |
|
For CVE-2015-4000: 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. 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
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References
Acknowledgement
Reported to IBM by The WeakDH team at https://weakdh.org
Change History
* 16 July 2015: 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
Review the IBM security bulletin disclaimer and definitions regarding your responsibilities for assessing potential impact of security vulnerabilities to your environment.
Internal Use Only
PSIRT 3489, Record 58524
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Document Information
Modified date:
04 February 2020
UID
swg21962398