KB15766 - Vulnerability in the PDF distiller of the BlackBerry Attachment Service for the BlackBerry Enterprise Server
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Environment
* BlackBerry® Enterprise Server software version 4.1 Service Pack 3 (4.1.3) through 4.1 Service Pack 5 (4.1.5)
Overview
This advisory describes a security issue that the BlackBerry Attachment Service component of the BlackBerry Enterprise Server is susceptible to. The issue relates to a known vulnerability in the PDF distiller component of the BlackBerry Attachment Service that affects how the BlackBerry Attachment Service processes PDF files.
This vulnerability has a Common Vulnerability Scoring System (CVSS) score of 9.0.
Problem
A security vulnerability in the PDF distiller of the BlackBerry Attachment Service could enable a malicious individual to use a specially crafted PDF file attachment in an email message to cause arbitrary code to execute on the computer that the BlackBerry Attachment Service runs on. If a BlackBerry smartphone user on a BlackBerry Enterprise Server opens and views the specially crafted PDF file attachment on the BlackBerry smartphone, the arbitrary code execution could compromise the computer.
Resolution
This issue has been escalated internally to our development team. No resolution time frame is currently available.
Workaround
Note: As a mobile device best practice, Research In Motion (RIM) recommends that BlackBerry smartphone users open attachments from trusted sources only.
Prevent the BlackBerry Attachment Service from processing PDF files in a BlackBerry Enterprise Server environment
You can prevent the BlackBerry Attachment Service from processing PDF files by editing the list of file format extensions that the BlackBerry Attachment Service opens, and then preventing the PDF attachment distiller from running on the BlackBerry Attachment Service.
To remove the PDF file extension from the list of supported file format extensions, complete the following actions:
1. From the Windows® Desktop, open the BlackBerry Server Configuration tool.
2. Click the Attachment Server tab.
3. In the Format Extensions field, delete pdf: from the colonxxx8211;delimited list of extensions.
4. Click Apply.
5. Click OK.
Until you prevent the PDF attachment distiller from running, the BlackBerry Attachment Service still detects a PDF file with a renamed extension (in other words, its extension is not .pdf) and attempts to process the file automatically. To prevent the PDF attachment distiller from running, complete the following actions:
1. On the Windows Desktop, open the BlackBerry Server Configuration tool.
2. Click the Attachment Server tab.
3. In the Configuration Option drop-down list, select Attachment Server.
4. In the Distiller Settings section, next to the distiller name Adobe PDF, clear the check box in the Enabled column.
5. Click Apply.
6. Click OK.
7. On the Windows Desktop, in Administrative Tools, open Services.
8. Right-click BlackBerry Attachment Service and click Stop.
9. Right-click BlackBerry Attachment Service and click Start.
10. Close Services.
In Microsoft® Exchange and Novell® GroupWise® environments, complete the following additional steps:
1. On the Windows Desktop, in Administrative Tools, open Services.
2. Right-click BlackBerry Dispatcher and click Stop.
3. Right-click BlackBerry Dispatcher and click Start.
4. Close Services.
Important: Restarting certain BlackBerry Enterprise Server services will delay email message delivery to BlackBerry smartphones. For more information, see
KB04789.
In IBM® Lotus® Domino® environments, complete the following additional steps:
1. Open the IBM Lotus Domino Administrator.
2. Click the Server tab.
3. Click the Status tab.
4. Click Server Console.
5. In the Domino Command field, type tell BES quit and press ENTER.
6. In the Domino Command field, type load BES and press ENTER.
7. Close the IBM Lotus Domino Administrator.
Additional Information
You can install the BlackBerry Attachment Service on a remote computer and then place that computer on its own network segment to prevent the spread of potential attacks from the BlackBerry Attachment Service to another computer within your organizationxxx8217;s network. In a segmented network, attacks are isolated and contained on a single area of the network. Using segmented network architecture is designed to improve the security and performance of the BlackBerry Attachment Service network segment by filtering out attachment data that is not destined for other network segments. For more information about placing the BlackBerry Enterprise Solution components in a network architecture that is segmented to prevent the spread of potential malware attacks, see Placing the BlackBerry Enterprise Solution in a Segmented Network.
Visit
BlackBerry - BlackBerry Enterprise Solution | Wireless Network Security for Corporate Data for more information on BlackBerry security.
CVSS is a vendor agnostic, industry open standard designed to convey the severity of vulnerabilities. CVSS scores may be used to determine the urgency for update deployment within an organization. CVSS scores range from 0.0 (no vulnerability) to 10.0 (critical). RIM uses CVSS in vulnerability assessments to present an immutable characterization of security issues. RIM assigns all security relevant issues a non-zero score.