Security Bulletin: IBM Security Access Manager for Web High CPU utilization (CVE-2014-0963)

Summary

The Reverse Proxy component in all versions of IBM Security Access Manager for Web is affected by a problem in which, under very specific conditions, CPU utilization can rapidly increase and not decrease. This issue is related to the SSL implementation in IBM Security Access Manager (ISAM) for Web.

Vulnerability Details

CVE ID:
CVE-2014-0963

DESCRIPTION:
The Reverse Proxy component in all versions of IBM Security Access Manager for Web is affected by a problem with the handling of certain SSL messages. The TLS implementation in a component of the Reverse Proxy can, under very specific conditions, cause CPU utilization to rapidly increase and not decrease. The situation occurs only in a certain error case that causes a single thread to begin looping. If this happens multiple times, more threads will begin to loop and an increase in CPU utilization will be seen. This could ultimately result in CPU exhaustion and unresponsiveness of IBM Security Access Manager for Web and other software running on the affected system.

This issue can affect the availability of the system, but does not impact system confidentiality or integrity. This vulnerability can be remotely exploited, authentication is not required and the exploit is moderately complex.

To determine if your systems are being affected by this issue, you can monitor the CPU utilization of your ISAM for Web instances.

CVSS:
CVSS Base Score: 7.1
CVSS Temporal Score: See <https://exchange.xforce.ibmcloud.com/vulnerabilities/92844&gt; for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:M/Au:N/C:N/I:N/A:C)

Affected Products and Versions

• All versions of IBM Security Access Manager for Web, both software and appliance: 7.0, 8.0

Remediation/Fixes

IBM has provided patches for all affected versions. Follow the installation instructions in the README files included with the patch.

Workarounds and Mitigations

Methods for ISAM for Web 7.0 software version

Method One: Monitor CPU utilization of your WebSEAL instances. If utilization becomes abnormally high, stop and restart the affected instance.

**Method Two:**Enable SSLv3 and disable all versions of TLS used by WebSEAL. To do this, perform these steps for every WebSEAL instance in your environment:

1. In the [ssl] stanza of the WebSEAL instance configuration file, enable SSLv3 by setting the following parameter:
   disable-ssl-v3 = no
2. In the [ssl] stanza of the WebSEAL instance configuration file, disable all versions of TLS by setting every parameter that starts with “disable-tls” to "yes"
3. Restart the WebSEAL instance

Methods for all ISAM for Web appliance versions

Method One: Monitor CPU utilization of your ISAM for Web appliance. From the Monitor main menu item, select System Graphs | CPU. If utilization becomes abnormally high, stop and restart all Reverse Proxy instances.

Method Two: Enable SSLv3 and disable all versions of TLS used by each Reverse Proxy instance. To do this, perform these steps for every Reverse Proxy instance in your environment:

1. In the [ssl] stanza of the Reverse Proxy instance configuration file, enable SSLv3 by setting the following parameter:
   disable-ssl-v3 = no
2. In the [ssl] stanza of the Reverse Proxy configuration file, disable all versions of TLS by setting every parameter that starts with “disable-tls” to “yes”
3. Save your changes and deploy.