Security Bulletin: Vulnerabilities in Bash affect IBM/Cisco Switches and Directors (CVE-2014-6271, CVE-2014-7169, CVE-2014-7186, CVE-2014-7187, CVE-2014-6277, CVE-2014-6278)

Summary

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/Cisco switches and directors.

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 http://xforce.iss.net/xforce/xfdb/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, 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 http://xforce.iss.net/xforce/xfdb/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
CVSS Temporal Score: See http://xforce.iss.net/xforce/xfdb/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
CVSS Temporal Score: See http://xforce.iss.net/xforce/xfdb/96238 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

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, 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 http://xforce.iss.net/xforce/xfdb/96686 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (AV:N/AC:L/Au:N/C:C/I:C/A:C)

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 http://xforce.iss.net/xforce/xfdb/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

The Following are IBM/Cisco Switches and Directors:

IBM MTM:

9710-E01MDS 9250i Multilayer Fabric Switch
9710-E08MDS 9710 Director
2054-E01MDS 9222i Multilayer Fabric Switch
2054-E04(2062-D04) MDS 9506 Multilayer Director
**2054-E11 (**2062-E11) MDS 9513 Multilayer Director **2054-E07 **(2062-D07) MDS 9509 Multilayer Director **2053-424 **(2417-C24) MDS 9124 Fabric Switch **2053-434 **(2053-S34) MDS 9134 Fabric Switch **2417-C48 **MDS 9148 Fabric Switch **3722-S51 **5010 Switch **3722-S52 **5020 Switch

Remediation/Fixes

IBM recommends that you remediate the Bash vulnerability by updating to the following code release.

NX-OS Release 6.2(9a)

Release Information:
<http://www.cisco.com/c/en/us/td/docs/switches/datacenter/mds9000/sw/6_2/release/notes/nx-os/mds_nxos_rn_629a.html&gt;

NX-OS Release 5.2(8e)

Release Information:
<http://www.cisco.com/c/en/us/td/docs/switches/datacenter/mds9000/sw/5_2/release/notes/nx-os/mds_nxos_rn_528e.html&gt;

IBM recommends that you review your entire environment to identify vulnerable releases of Bash including your Operating Systems and take appropriate mitigation and remediation actions. Please contact your Operating System provider for more information.

Workarounds and Mitigations

**Important note:**IBM strongly suggests that all System z customers subscribe to the System z Security Portal to receive the latest critical System z security and integrity service. If you are not subscribed, see the instructions on the System z Security web site. Security and integrity APARs and associated fixes will be posted to this portal. IBM suggests reviewing the CVSS scores and applying all security or integrity fixes as soon as possible to minimize any potential risk.