avahi security update (RHSA-2011-0436)

Original Release Date: May 18, 2011
Last Revised: July 28, 2015
Number: ASA-2011-153
Risk Level: Low
Advisory Version: 4.0
Advisory Status: Final

1. Overview:

Avahi is an implementation of the DNS Service Discovery and Multicast DNS specifications for Zero Configuration Networking. It facilitates service discovery on a local network. Avahi and Avahi-aware applications allow you to plug your computer into a network and, with no configuration, view other people to chat with, view printers to print to, and find shared files on other computers.

A flaw was found in the way the Avahi daemon (avahi-daemon) processed Multicast DNS (mDNS) packets with an empty payload. An attacker on the local network could use this flaw to cause avahi-daemon on a target system to enter an infinite loop via an empty mDNS UDP packet. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2011-1002 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 RHEL5 with the affected versions of avahi installed:
Product: Affected Version(s): Risk Level: Actions:
Avaya Communication Server 1000:
  • CS1000E
  • CS1000M
  • CS1000E/CS1000M Signaling Server
6.0 through 7.6 Low See recommended actions and Mitigating Factors table below. This advisory will not be addressed as no further releases are planned.
Avaya IQ 5.2 thru 5.2.5 Low Upgrade to 5.2.6 and install Patch 2 or later.
Avaya Aura® Presence Services 6.0, 6.1, 6.1.1 Low Upgrade to Presence 6.1.2 or later.
Avaya Aura® Session Manager 1.1, 5.2, 6.0, 6.1 Low Upgrade to Session Manager 6.2 or later.
Avaya Aura® System Manager 5.2, 6.0, 6.1 Low Upgrade to System Manager 6.2 or later.
Avaya Aura® System Platform 1.1, 6.0 Low Upgrade to System Platform 6.2 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-2011-1002
This is rated a Low Risk since only non-critical applications are affected.

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 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 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.
Voice Portal Depending on the Operating System provided by customers, the affected package may be installed on the underlying Operating System supporting the Voice Portal 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 - May 18, 2011 - Initial Statement issued.
V 2.0 - September 18, 2012 - Updated Presence, SM, SMGR and SP actions.
V 3.0 - August 4, 2014 - Updated CS1000 affected versions and actions.
V 4.0 - July 28, 2015 - Updated IQ affected versions and actions, and set advisory 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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