ASA-2007-063 (RHSA-2007-0014)

kernel security update (RHSA-2007-0014)

Original Release Date: February 16, 2007
Last Revised: February 13, 2009
Number: ASA-2007-063
Risk Level: Medium
Advisory Version: 6.0
Advisory Status: Final

1. Overview:

The Linux kernel manages the communication between software and hardware as well as the hardware resources of a computer running the Linux operating system.

Red Hat has issued an updated version of the kernel packages for Enterprise Linux 4. Below is a list of the security issues fixed in the update as reported by Red Hat:

a flaw in the get_fdb_entries function of the network bridging support that allowed a local user to cause a denial of service (crash) or allow a potential privilege escalation.
an information leak in the _block_prepare_write function that allowed a local user to read kernel memory.
an information leak in the copy_from_user() implementation on s390 and s390x platforms that allowed a local user to read kernel memory.
a flaw in the handling of /proc/net/ip6_flowlabel that allowed a local user to cause a denial of service (infinite loop).
a flaw in the AIO handling that allowed a local user to cause a denial of service (panic).
a race condition in the mincore system core that allowed a local user to cause a denial of service (system hang).
a flaw in the ELF handling on ia64 and sparc architectures which triggered a cross-region memory mapping and allowed a local user to cause a denial of service.
a flaw in the dev_queue_xmit function of the network subsystem that allowed a local user to cause a denial of service (data corruption).
a flaw in the handling of CAPI messages over Bluetooth that allowed a remote system to cause a denial of service or potential code execution. This flaw is only exploitable if a privileged user establishes a connection to a malicious remote device.
a flaw in the listxattr system call that allowed a local user to cause a denial of service (data corruption) or potential privilege escalation. To successfully exploit this flaw the existence of a bad inode is required first.
a flaw in the __find_get_block_slow function that allowed a local privileged user to cause a denial of service.
various flaws in the supported filesystems that allowed a local privileged user to cause a denial of service.

The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the names CVE-2006-5751, CVE-2006-4813, CVE-2006-5174, CVE-2006-5619, CVE-2006-5754, CVE-2006-4814, CVE-2006-4538, CVE-2006-6535, CVE-2006-6106, CVE-2006-5753, CVE-2006-5757, CVE-2006-5823, CVE-2006-6053, CVE-2006-6054, and CVE-2006-6056 to these issues.

While this advisory deals with the kernel package from RedHat Enterprise Linux 4, the vulnerabilities in this advisory have been assessed against currently supported versions of Avaya Communications Manager (CM). As such, some of the responses may include versions of Avaya Communications Manager that do not run on RedHat Enterprise Linux 4 or on a 2.6 series kernel.

CM 2.x and CM 3.0, which use a 2.4 series Linux kernel, are only vulnerable to the mincore race condition ( CVE-2006-4814) listed above. As there is no known exploit for this issue and it would require someone with access to a user account on CM, Avaya has chosen to rate the impact of this ASA to CM 2.x and CM 3.0 as a Low Risk Level.

CM 3.1.x, which uses a 2.6 series Linux kernel, is vulnerable to all of the issues in this advisory including the potential privilege escalations in the get_fdb_entries issue ( CVE-2006-5751) and the listxattr-system-call issue ( CVE-2006-5753) listed above.

Avaya Messaging Storage Server has been marked as having a Low Risk Level as shell access is not available in an Avaya recommended default configuration.

More information about these vulnerabilities can be found in the security advisory issued by RedHat Linux:

https://rhn.redhat.com/errata/RHSA-2007-0014.html

2. Avaya System Products with kernel installed:

Product:	Affected Version(s):	Risk Level:	Actions:
Avaya S87XX/S8500/S8300	CM 2.x, CM 3.0, CM 3.1.3 and earlier, CM 4.0	Low Medium	For CM versions 2.x and 3.0, upgrade to CM 3.1.4 or a later version in the 3.1.x series. For CM 3.1.3 and earlier releases in the CM 3.1.x series, upgrade to CM 3.1.4 or a later version in the 3.1.x series. For CM 4.0, upgrade to CM 4.0.1 or later.
Avaya Messaging Storage Server	MSS 3.x	Low	Upgrade to MSS 4.0 or later.
Avaya CCS/SES	SES 2.0 - 3.x	Medium	Upgrade to SES 4.0 or later.
Avaya AES	AES 4.0	Medium	Upgrade to AES 4.0.1 or later.

Recommended Actions:
For all system products which use vulnerable versions of the kernel, Avaya recommends that customers restrict local and network access to the server. This restriction should be enforced through the use of physical security, firewalls, ACLs, VPNs, and other generally-accepted networking practices until such time as an update becomes available and can be installed.

3. Avaya Software-Only Products:

Avaya software-only products operate on general-purpose operating systems. Occasionally vulnerabilities may be discovered in the underlying operating system or applications that come with the operating system. These vulnerabilities often do not impact the software-only product directly but may threaten the integrity of the underlying platform.

In the case of this advisory Avaya software-only products are not affected by the vulnerability directly but the underlying Linux platform may be. Customers should determine on which Linux operating system the product was installed and then follow that vendors guidance.

4. Software-Only Products:

Product:	Affected Version(s):	Risk Level:	Actions:
CVLAN	All	None	Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the CVLAN application. The CVLAN application does not require the software described in this advisory.
Avaya Integrated Management Suite(IMS)	All	None	Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the IMS application. The IMS application does not require the software described in this advisory.

Recommended Actions:
Avaya recommends that customers follow recommended actions supplied by RedHat Linux.

5. Additional Information:

Additional information may also be available via the Avaya support website and through your Avaya account representative. Please contact your Avaya product support representative, or dial 1-800-242-2121, with any questions.

6. Disclaimer:

ALL INFORMATION IS BELIEVED TO BE CORRECT AT THE TIME OF PUBLICATION AND IS PROVIDED "AS IS". AVAYA INC., ON BEHALF ITSELF AND ITS SUBSIDIARIES AND AFFILIATES (HEREINAFTER COLLECTIVELY REFERRED TO AS "AVAYA"), DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE AND FURTHERMORE, AVAYA MAKES NO REPRESENTATIONS OR WARRANTIES THAT THE STEPS RECOMMENDED WILL ELIMINATE SECURITY OR VIRUS THREATS TO CUSTOMERS' SYSTEMS. IN NO EVENT SHALL AVAYA BE LIABLE FOR ANY DAMAGES WHATSOEVER ARISING OUT OF OR IN CONNECTION WITH THE INFORMATION OR RECOMMENDED ACTIONS PROVIDED HEREIN, INCLUDING DIRECT, INDIRECT, CONSEQUENTIAL DAMAGES, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF AVAYA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

THE INFORMATION PROVIDED HERE DOES NOT AFFECT THE SUPPORT AGREEMENTS IN PLACE FOR AVAYA PRODUCTS. SUPPORT FOR AVAYA PRODUCTS CONTINUES TO BE EXECUTED AS PER EXISTING AGREEMENTS WITH AVAYA.

7. Revision History:

V 1.0 - February 19, 2007 - Initial Statement issued.
V 2.0 - March 12, 2007 - Updated MSS Risk Level to Low based on further review. Changed affected AES version from 3.1 to 4.0 based on further review. Clarified the issues that affect the different versions of CM and changed the Risk Level rating of CM 2.x and CM 3.0 to Low.
V 3.0 - May 14, 2007 - Updated Communication Manager Recommended Actions to indicate a fix is available for this advisory in CM 3.1.4 and later.
V 4.0 - October 9, 2007 - Updated Recommended Actions for Communication Manager and AES.
V 5.0 - February 11, 2008 - Updated Recommended Actions for Avaya CCS/SES.
V 6.0 - February 13, 2009 - Updated Recommended Actions for MSS and ASA status to final.

Send information regarding any discovered security problems with Avaya products to either the contact noted in the product's documentation or [email protected].

© 2007 Avaya Inc. All Rights Reserved. All trademarks identified by the ® or ™ are registered trademarks or trademarks, respectively, of Avaya Inc. All other trademarks are the property of their respective owners.