Security Bulletin: Vulnerabilities in Bash affect IBM Workload Deployer (CVE-2014-6271, CVE-2014-7169, CVE-2014-7186, CVE-2014-7187, CVE-2014-6277, CVE-2014-6278)

Summary

Bash is available in Red Hat Linux virtual machine images that can be deployed by using IBM Workload Deployer. Six Bash vulnerabilities were disclosed in September 2014. This bulletin addresses the vulnerabilities that have been referred to as “Bash Bug” or “Shellshock” and two memory corruption vulnerabilities. Bash is used by IBM Workload Deployer.

Vulnerability Details

CVE-ID: CVE-2014-6271

DESCRIPTION: GNU Bash could allow a remote attacker to execute arbitrary commands on the system, caused by an error when evaluating specially crafted environment variables passed to it by the Bash functionality. An attacker could exploit this vulnerability to write to files and execute arbitrary commands on the system.

CVSS Base Score: 10.0
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/96153 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

CVE-ID: CVE-2014-7169

DESCRIPTION: GNU Bash could allow a remote attacker to execute arbitrary commands on the system, caused by an incomplete fix related to malformed function definitions in the values of environment variables. An attacker could exploit this vulnerability using attack vectors involving the ForceCommand feature in OpenSSH sshd, and the mod_cgi and mod_cgid modules in the Apache HTTP Server to write to files and execute arbitrary commands on the system.

CVSS Base Score: 10.0
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/96209 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

CVE-ID: CVE-2014-7186

DESCRIPTION: GNU Bash could allow a remote attacker to execute arbitrary code on the system, caused by an out-of-bounds memory access while handling redir_stack. An attacker could exploit this vulnerability to execute arbitrary code on the system or cause a denial of service.

CVSS Base Score: 10.0
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/96237 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

CVE-ID: CVE-2014-7187

DESCRIPTION: GNU Bash could allow a remote attacker to execute arbitrary code on the system, caused by an off-by-one error when handling deeply nested flow control constructs. An attacker could exploit this vulnerability to execute arbitrary code on the system or cause a denial of service.

CVSS Base Score: 10.0
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/96238 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

CVE-ID: CVE-2014-6277

DESCRIPTION: GNU Bash could allow a remote attacker to execute arbitrary code on the system, caused by an incomplete fix related to the failure to properly parse function definitions in the values of environment variables. An attacker could exploit this vulnerability using attack vectors involving the ForceCommand feature in OpenSSH sshd, and the mod_cgi and mod_cgid modules in the Apache HTTP Server to execute arbitrary code on the system or cause a denial of service.

CVSS Base Score: 10.0
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/96686 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

CVE-ID: CVE-2014-6278

DESCRIPTION: GNU Bash could allow a remote attacker to execute arbitrary code on the system, caused by an incomplete fix related to the parsing of user scripts. An attacker could exploit this vulnerability to execute arbitrary code on the system or cause a denial of service.

CVSS Base Score: 10.0
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/96687 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

Affected Products and Versions

All versions of IBM Workload Deployer 3.1 and later fix packs

Remediation/Fixes

The solution is to apply the fixes with the following direction:

Upgrade the deployed virtual machines by using one of the following two methods:

Option 1: Update the virtual machine by using an eFix provided by IBM:

• Download the eFix from IBM Fix Central (see the following link):

http://www-933.ibm.com/support/fixcentral/swg/selectFixes?parent=ibm~WebSphere&product=ibm/WebSphere/IBM+Workload+Deployer&release=All&platform=All&function=fixId&fixids=HV_RHEL6_X64_PATCHES_EFIX&includeSupersedes=0

• Import the eFix into the IBM Workload Deployer Emergency Fix catalog.

• For deployed instances, apply this Emergency Fix on the virtual machine. Bash is upgraded to version bash-4.1.2-15.e16_5.2.

Option 2: Upgrade the virtual machine with fixes obtained from Red Hat

• Contact Red Hat to obtain fixes and install these fixes directly on the deployed virtual machines as needed.

For images, you must extend and capture the image by using the following general procedure:

1. Import the eFix into the IBM Workload Deployer Emergency Fix catalog.
2. From the image catalog, select the image and click “Extend.”
3. After the image extend operation completes succcessfully, click Service from the deployed virtual machine.
4. Apply this emergency fix.
5. From the image catalog, capture the image.

Use this newly captured image for future deployment.

Workarounds and Mitigations

None known