BSRT-2013-008 Vulnerability in Webkit browser engine impacts BlackBerry Z10 smartphone and BlackBerry PlayBook tablet software

Article ID: KB34779

Type:   BlackBerry Security Advisory

First Published: 09-10-2013

Last Modified: 09-10-2013

 
CollapseOverview

This advisory addresses a WebKit remote code execution vulnerability that is not currently being exploited but affects BlackBerry® Z10 smartphone and BlackBerry® PlayBook™ tablet customers.  BlackBerry customer risk is limited by the BlackBerry® 10 OS and the BlackBerry® tablet OS design, which restricts an application's access to system resources and the private data of other applications. Successful exploitation requires an attacker to create a malicious website or compromise a legitimate website, and requires that a BlackBerry Z10 smartphone or BlackBerry tablet user view a webpage containing the malicious JavaScript content.  If the requirements are met for exploitation, an attacker could potentially execute code in the BlackBerry Browser. After installing the recommended software update, affected BlackBerry Z10 customers and BlackBerry tablet customers will be fully protected from this vulnerability.

ExpandWho should read this advisory?
  • BlackBerry Z10 smartphone users
  • BlackBerry PlayBook tablet users
  • IT administrators who deploy BlackBerry Z10 smartphones in an enterprise
  • IT administrators who deploy BlackBerry PlayBook tablets in an enterprise
ExpandWho should apply the software fix(es)?
  • BlackBerry Z10 smartphone users
  • BlackBerry PlayBook tablet users
  • IT administrators who deploy BlackBerry Z10 smartphones in an enterprise
  • IT administrators who deploy BlackBerry PlayBook tablets in an enterprise
ExpandMore Information

Have any BlackBerry customers been subject to an attack that exploits these vulnerabilities?
BlackBerry is not aware of any attacks on, or specifically targeting, BlackBerry Z10 smartphone and BlackBerry tablet customers using this vulnerability.

What factors affected the release of this security advisory?
This advisory addresses a publicly known WebKit vulnerability. BlackBerry publishes full details of a software update in a security advisory after the fix is available to the majority of our customers and wireless service provider partners. Publishing this advisory ensures that all of our customers can protect themselves by either updating their software, employing available workarounds or implementing mitigations included in this advisory until the software update is available to them. Customers for whom the software update is not yet available should contact their wireless service provider to request BlackBerry 10 OS version 10.0.10.261 or later and/or BlackBerry Tablet OS version 2.1.0.1753 or later.

Where can I read more about BlackBerry Z10 smartphone and BlackBerry PlayBook tablet security?
Read the BlackBerry PlayBook Tablet Security Feature Overview and the BlackBerry Enterprise Service 10 Security Technical Overview for more information on security features in the BlackBerry Z10 smartphone and BlackBerry PlayBook tablet.

Where can I read more about the security of BlackBerry products and solutions?
Visit http://us.blackberry.com/business/topics/security.html for more information on BlackBerry security.

CollapseAffected Software and Resolutions

Customers can read the following lists to determine if their BlackBerry Z10 smartphone or BlackBerry PlayBook tablet is affected.

ExpandAffected Software
  • BlackBerry 10 OS earlier than version 10.0.10.261 except versions 10.0.9.2709 and 10.0.9.2743
  • BlackBerry PlayBook tablet earlier than version 2.1.0.1753
ExpandNon-Affected Software
  • BlackBerry 10 OS version 10.0.9.2743 
  • BlackBerry 10 OS version 10.0.9.2709
  • BlackBerry 10 OS version 10.0.10.261 or later 
  • BlackBerry 10 OS version 10.1 
  • BlackBerry 7 OS and earlier 
  • BlackBerry® PlayBook™ tablet software version 2.1.0.1753
ExpandAre BlackBerry smartphones affected?
Yes; only BlackBerry Z10 smartphones running BlackBerry 10 OS earlier than version 10.0.10.261 are affected, except versions 10.0.9.2709 and 10.0.9.2743.
ExpandResolution

BlackBerry has issued a fix for this vulnerability, which is included in BlackBerry 10 OS versions 10.0.10.261 and later, as well as 10.0.9.2709 and 10.0.9.2743, and in BlackBerry tablet software version 2.1.0.1753 and later. These software updates resolve this vulnerability on affected versions of BlackBerry Z10 smartphones and the BlackBerry tablet. Customers should update their BlackBerry Z10 smartphone to BlackBerry 10 OS version 10.0.10.261 or later and update their BlackBerry tablet software to version 2.1.0.1753 or later to be fully protected from this issue.

Note: Customers who are running a BlackBerry 10 OS version earlier than 10.0.10.261 (except versions 10.0.9.2709 or 10.0.9.2743) and/or a BlackBerry tablet OS version earlier than 2.1.0.1753 but do not see a software update notification, and whose device indicates that the software is up to date, should contact their wireless service provider to request BlackBerry 10 OS version 10.0.10.261 or later and/or BlackBerry Tablet OS version 2.1.0.1753 or later.

See the Mitigations section of this advisory for information on how to mitigate potential risk until the software update is available for all customers.

Update by Accessing the Software Update Notification

BlackBerry Z10 smartphones and BlackBerry PlayBook tablets use notifications to keep customers informed about software updates. When a new software update notification is available, it appears in the status ribbon at the top of the screen on the BlackBerry PlayBook tablet, and within the Notifications section of the BlackBerry Hub on a BlackBerry Z10 smartphone.
Simply view the notifications and follow the steps to access the latest software update notification and complete the software update.

Manually Check for Software Updates on BlackBerry Z10 smartphones

  1. From the home screen, swipe down from the top of the screen.
  2. Tap Settings, then Software Updates.
  3. Tap Check for Updates.

Manually Check for Software Updates on the BlackBerry PlayBook tablet

  1. From the home screen, swipe down from the top of the screen.
  2. Tap Software Updates.
  3. Tap Check for Updates.

Customers can also update their BlackBerry Z10 smartphone software using BlackBerry® Link and their BlackBerry tablet software using BlackBerry® Desktop Software. For more information, see the Help documentation for BlackBerry Link or the Help documentation for BlackBerry Desktop Software.

After customers update their software, the screen will indicate that BlackBerry 10 OS version 10.0.10.261 or later and BlackBerry Tablet OS version 2.1.0.1753 is installed on the device.

ExpandMore Information

How can I find out what version of the BlackBerry 10 OS I am running?

For BlackBerry Z10 smartphones:

  1. From the home screen, swipe down from the top of the screen.
  2. Tap Settings.
  3. Tap About, and view the OS Version or Software Release field in the OS settings.

For the BlackBerry PlayBook tablet:

  1. From the home screen, swipe down from the top of the screen.
  2. Tap About, and view the OS Version.

Are new (still in the box) BlackBerry Z10 smartphones and BlackBerry PlayBook tablets exposed to this vulnerability?
During the initial setup process, both the BlackBerry Z10 smartphone and the BlackBerry PlayBook tablet will download and install the latest version of the OS available from the customer’s carrier. The fix for this vulnerability is included in all versions of the BlackBerry Z10 smartphone software after version 10.0.10.261, as well as versions 10.0.9.2709 or 10.0.9.2743, and the BlackBerry tablet software after 2.1.0.1753.

Note: If customers are running a BlackBerry 10 OS version earlier than 10.0.10.261 (except versions 10.0.9.2709 or 10.0.9.2743) and/or a BlackBerry Tablet OS version earlier than 2.1.0.1753 but do not see a software update notification but their device indicates that the software is up to date, customers can contact their wireless service provider to request BlackBerry 10 OS version 10.0.10.261 and/or BlackBerry Tablet OS version 2.1.0.1753 or later.

Are BlackBerry Q10 or Q5 smartphones exposed to this vulnerability?
No. The fix for this vulnerability is included in all versions of the BlackBerry Q10 and Q5 smartphone software.

Does the BlackBerry Z10 smartphone and/or BlackBerry PlayBook tablet force me to update my software?
No, customer action is required to update the software. BlackBerry Z10 smartphones and BlackBerry PlayBook tablets use notifications to keep customers informed about software updates and provide instructions to help customers install a software update. Customers can also manually check for software updates. See the Resolution section of this advisory for BlackBerry device software update instructions.

CollapseVulnerability Information

A vulnerability exists in the JavaScriptCore component of the open source WebKit browser engine included in affected versions of the BlackBerry Z10 smartphone and BlackBerry PlayBook tablet. The JavaScriptCore component interprets and executes JavaScript in the browser. Successful exploitation of the vulnerability could result in an attacker executing code  in the context of the web browser.

In order to exploit this vulnerability, an attacker must place maliciously crafted JavaScript on a website; the website could be an otherwise legitimate website that the attacker has compromised. An example of a website that could be compromised is a site that accepts or hosts user-provided JavaScript content or advertisements. The attacker must then persuade the user to access the webpage containing maliciously crafted JavaScript using the BlackBerry Z10 smartphone and/or the BlackBerry PlayBook tablet’s browser.

This vulnerability has a Common Vulnerability Scoring System (CVSS) score of 6.8. For a description of the WebKit security issue that this security advisory addresses, see the CVE® identifier CVE-2013-0999.

Mitigations

BlackBerry Z10 smartphone and PlayBook

The capabilities and permissions of BlackBerry PlayBook tablet and BlackBerry Z10 smartphone applications are restricted using a technique called sandboxing. Sandboxing limits the impact of vulnerabilities in applications to the confidentiality or integrity of other applications or the private data associated with them.

In a web-based attack scenario, an attacker could host a specially crafted website that is designed to exploit these vulnerabilities through the BlackBerry Browser and then convince a user to view the website, or the attacker could take advantage of compromised websites and websites that accept or host user-provided content or advertisements. These websites could contain specially crafted content that could exploit these vulnerabilities. In all cases, however, an attacker would have no way to force users to view the attacker-controlled content.

ExpandWorkarounds

BlackBerry recommends that all users apply the available software update to fully protect their BlackBerry Z10 smartphone, and/or BlackBerry PlayBook tablets.

All workarounds should be considered temporary measures for customers to employ if they cannot install the update immediately or must perform standard testing and risk analysis. BlackBerry recommends that customers without these requirements install the update to secure their systems.

BlackBerry PlayBook
For users that are unable to upgrade at this time, this risk can be mitigated by temporarily disabling the use of JavaScript in the browser on the BlackBerry PlayBook tablet (in the browser, tap Options > Content, and set Enable JavaScript to Off).
Important: Turning off JavaScript in the browser will impact the ability to view content on some web pages, and result in a diminished browsing experience.

Once users have upgraded their BlackBerry tablet software, they can re-enable JavaScript content in the browser (in the browser, tap Options > Content, and set Enable JavaScript to On).

BlackBerry Z10 smartphone
There are no workarounds for the BlackBerry Z10 smartphone regarding this vulnerability. BlackBerry recommends that all users apply the available software update to fully protect their BlackBerry Z10 smartphone.

CollapseDefinitions

CVE

Common Vulnerabilities and Exposures (CVE) is a dictionary of common names (CVE Identifiers) for publicly known information security vulnerabilities maintained by the MITRE Corporation.

CVSS

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 can range from 0.0 (no vulnerability) to 10.0 (critical). BlackBerry uses CVSS in vulnerability assessments to present an immutable characterization of security issues. BlackBerry assigns all relevant security issues a non-zero score. Customers performing their own risk assessments of vulnerabilities that may impact them can benefit from using the same industry-recognized CVSS metrics.

CollapseAcknowledgements
BlackBerry acknowledges the following security researcher for reporting CVE-2013-0999 through ZDI: pa_kt (twitter.com/pa_kt).
CollapseChange Log

09-10-2013

Initial publication.

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