ruby security update (RHSA-2008-0897)

Original Release Date: October 22, 2008
Last Revised: October 22, 2008
Number: ASA-2008-424
Risk Level: None
Advisory Version: 1.0
Advisory Status: Final

1. Overview:

Ruby is an interpreted scripting language for quick and easy object-oriented programming.

The Ruby DNS resolver library, resolv.rb, used predictable transaction IDs and a fixed source port when sending DNS requests. A remote attacker could use this flaw to spoof a malicious reply to a DNS query. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2008-3905 to this issue.

Ruby's XML document parsing module (REXML) was prone to a denial of service attack via XML documents with large XML entity definitions recursion. A specially-crafted XML file could cause a Ruby application using the REXML module to use an excessive amount of CPU and memory. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2008-3790 to this issue.

An insufficient "taintness" check flaw was discovered in Ruby's DL module, which provides direct access to the C language functions. An attacker could use this flaw to bypass intended safe-level restrictions by calling external C functions with the arguments from an untrusted tainted inputs. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2008-3657 to this issue.

A denial of service flaw was discovered in WEBrick, Ruby's HTTP server toolkit. A remote attacker could send a specially-crafted HTTP request to a WEBrick server that would cause the server to use an excessive amount of CPU time. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2008-3656 to this issue.

A number of flaws were found in the safe-level restrictions in Ruby. It was possible for an attacker to create a carefully crafted malicious script that can allow the bypass of certain safe-level restrictions. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2008-3655 to this issue.

A denial of service flaw was found in Ruby's regular expression engine. If a Ruby script tried to process a large amount of data via a regular expression, it could cause Ruby to enter an infinite-loop and crash. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CVE-2008-3443 to this issue.

No Avaya system products using RHEL4 are vulnerable, as ruby is not installed by default.

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

2. Avaya System Products using RHEL4 with ruby installed: None

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:
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.
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:
In the event that the affected package is installed, Avaya recommends that customers follow recommended actions supplied by RedHat 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 - October 22, 2008 - Initial Statement issued.

Send information regarding any discovered security problems with Avaya products to either the contact noted in the product's documentation or securityalerts@avaya.com.

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