kernel security and bug fix update (RHSA-2012-0743)

Original Release Date: June 20, 2012
Last Revised: January 8, 2014
Number: ASA-2012-259
Risk Level: Medium
Advisory Version: 2.0
Advisory Status: Final

1. Overview:

The kernel packages contain the Linux kernel, the core of any Linux operating system.

This update fixes the following security issues:

A local, unprivileged user could use an integer overflow flaw in drm_mode_dirtyfb_ioctl() to cause a denial of service or escalate their privileges. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-0044 to this issue.

A buffer overflow flaw was found in the macvtap device driver, used for creating a bridged network between the guest and the host in KVM (Kernel-based Virtual Machine) environments. A privileged guest user in a KVM guest could use this flaw to crash the host. Note: This issue only affected hosts that have the vhost_net module loaded with the experimental_zcopytx module option enabled (it is not enabled by default), and that also have macvtap configured for at least one guest. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-2119 to this issue.

When a set user ID (setuid) application is executed, certain personality flags for controlling the application's behavior are cleared (that is, a privileged application will not be affected by those flags). It was found that those flags were not cleared if the application was made privileged via file system capabilities. A local, unprivileged user could use this flaw to change the behavior of such applications, allowing them to bypass intended restrictions. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-2123 to this issue.

It was found that the data_len parameter of the sock_alloc_send_pskb() function in the Linux kernel's networking implementation was not validated before use. A privileged guest user in a KVM guest could use this flaw to crash the host or, possibly, escalate their privileges on the host. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-2136 to this issue.

A buffer overflow flaw was found in the setup_routing_entry() function in the KVM subsystem of the Linux kernel in the way the Message Signaled Interrupts (MSI) routing entry was handled. A local, unprivileged user could use this flaw to cause a denial of service or, possibly, escalate their privileges. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-2137 to this issue.

A race condition was found in the Linux kernel's memory management subsystem in the way pmd_none_or_clear_bad(), when called with mmap_sem in read mode, and Transparent Huge Pages (THP) page faults interacted. A privileged user in a KVM guest with the ballooning functionality enabled could potentially use this flaw to crash the host. A local, unprivileged user could use this flaw to crash the system. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-1179 to this issue.

A flaw was found in the way device memory was handled during guest device removal. Upon successful device removal, memory used by the device was not properly unmapped from the corresponding IOMMU or properly released from the kernel, leading to a memory leak. A malicious user on a KVM host who has the ability to assign a device to a guest could use this flaw to crash the host. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-2121 to this issue.

A flaw was found in the Linux kernel's Reliable Datagram Sockets (RDS) protocol implementation. A local, unprivileged user could use this flaw to cause a denial of service. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-2372 to this issue.

A race condition was found in the Linux kernel's memory management subsystem in the way pmd_populate() and pte_offset_map_lock() interacted on 32-bit x86 systems with more than 4GB of RAM. A local, unprivileged user could use this flaw to cause a denial of service. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2012-2373 to this issue.

More information about these vulnerabilities can be found in the security advisory issued by Red Hat:

2. Avaya System Products using a modified version of RHEL6 with affected components/packages installed:

Product: Affected Version(s): Risk Level: Actions:
Avaya Aura® Experience Portal 6.0, 6.0 SP1 Medium Upgrade to 6.0 SP2 or later.

Recommended Actions for System Products:
Avaya strongly recommends that customers follow networking and security best practices by implementing firewalls, ACLs, physical security or other appropriate access restrictions. Though Avaya believes such restrictions should always be in place, risk to Avaya products and the surrounding network from this potential vulnerability may be mitigated by ensuring these practices are implemented until such time as an Avaya provided product update or the recommended Avaya action is applied. Further restrictions as deemed necessary based on the customer's security policies may be required during this interim period, but customers should not modify the System Product operating system or application unless the change is approved by Avaya. Making changes that are not approved may void the Avaya product service contract.

Mitigating Factors:

When determining risk, Avaya takes into account many factors as outlined by Avaya's Security Vulnerability Classification Policy. The following table describes factors that mitigate the risk of specific vulnerabilities for affected Avaya products:

Vulnerability Mitigating Factors
CVE-2012-0044
CVE-2012-2123
CVE-2012-2372
CVE-2012-2373
These are rated a Medium Risk since a local, unprivileged user could take advantage of these vulnerabilities to cause a denial of service or escalate their privileges.
CVE-2012-1179
CVE-2012-2119
CVE-2012-2121
CVE-2012-2136
CVE-2012-2137
There is no risk to EP for these vulnerabilities since KVM is not used.

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 vendor's guidance.

Product: Actions:
Avaya Aura® Application Enablement Services 4.x/5.x Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the AES application.
CVLAN Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the CVLAN application.
Avaya Aura® Experience Portal Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the EP application.
Avaya Integrated Management Suite (IMS) Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the IMS application.
Avaya Aura® Presence Services Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the PS application.
Avaya Secure Access Link Gateway Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the SAL Gateway application.
Avaya Aura® System Manager 1.0 Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the SMGR application.
Avaya Voice Portal Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the VP application.

Recommended Actions for Software-Only Products:
In the event that the affected package is installed, Avaya recommends that customers follow recommended actions supplied by Red Hat regarding their Enterprise Linux.

4. 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.

5. 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 BUT NOT LIMITED TO 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, INCIDENTAL, STATUTORY, 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.

6. Revision History:

V 1.0 - June 20, 2012 - Initial Statement issued.
V 2.0 - January 8, 2014 - Updated EP affected versions and actions 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].

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