Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Perimeter

5/31/2012
04:47 PM
Tom Parker
Tom Parker
Commentary
50%
50%

State-Sponsored Backdoor Or Programming Faux Pas?

Backdoor in Android-based handsets sponsor, bad programming, or a #win for Apple's stringent application QA process?

Earlier this month, a Pastebin post that detailed the presence of a possible backdoor on the Android-based ZTE Score M mobile phone handset caught my attention. For those of you who are unfamiliar, ZTE (formally Zhongxing Telecommunication Equipment Corp.) is a telecommunications manufacturing company and, like the more well-known Huawei, is based out of Shenzhen, China.

The original report of the purported backdoor documents a said root application that could be forked by any nonprivileged process that has file system access to obtain a super-user shell. In order to obtain a shell, the binary (named sync_agent) must be passed a super-secret parameter of "ztex1609523."

The post closes with the statement, "Nice backdoor, ZTE."

Given the geography of the vendor and the nature of the binary, the tweet stream, security forums, and press alike were pretty quick to pick up on this report, speculating over the possible intent of the binary. As it turns out, the offending component was an apk (or Android package) specifically built for the U.S. cellular carrier MetroPCS.

On closer analysis, the "helper" application is dropped by the package in order to facilitate the installation and removal of other software packages and the execution of a number of busybox commands, intended to further facilitate the management of the application. While unorthodox, analysis of the sync_agent binary neither indicates any additional malicious intent nor features any indications of a state-sponsored attack against users of a U.S.-based carrier as several blogs suggested earlier on.

Interestingly, analysis of the sync_agent actually indicates U.S. origin, given various tool-markings in the binary and various debug messages that indicate a native-English speaking author.

Although the binary is unlikely the work of a nation-state or super-criminal, it does bring back memories of BMG, the Sony "rootkit" that was all over the headlines in 2005. Essentially, Sony had included functionality within software distributed on its media that featured a device driver that implemented kernel hooks to hide files with certain extensions. While there was no real malicious intent there, it did raise questions as to how that might expose users to malicious software that leverages the Sony code to prevent detection.

Similarly, the ZTE Metro PCS Android package fails to use accepted Droid development doctrine and built-in APIs for performing privileged operations; as a result, it absolutely exposed users to some significant risk due to the opportunity for malicious software to leverage the helper binary for nefarious purposes.

While the number of impacted devices seems to be minimal, it does further demonstrate the need for restraint when characterizing rumors of malicious code, and a clear need for better QA of Android applications. It also shows what the future might hold in terms of truly malicious Android applications created by state (and other) sponsors entering the supply chain.

Tom Parker is Chief Technology Officer at FusionX.

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
News
US Formally Attributes SolarWinds Attack to Russian Intelligence Agency
Jai Vijayan, Contributing Writer,  4/15/2021
News
Dependency Problems Increase for Open Source Components
Robert Lemos, Contributing Writer,  4/14/2021
News
FBI Operation Remotely Removes Web Shells From Exchange Servers
Kelly Sheridan, Staff Editor, Dark Reading,  4/14/2021
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win an Amazon Gift Card! Click Here
Latest Comment: Tell him only Kevin Mitnick and the President know the launch codes.
Current Issue
2021 Top Enterprise IT Trends
We've identified the key trends that are poised to impact the IT landscape in 2021. Find out why they're important and how they will affect you today!
Flash Poll
How Enterprises are Developing Secure Applications
How Enterprises are Developing Secure Applications
Recent breaches of third-party apps are driving many organizations to think harder about the security of their off-the-shelf software as they continue to move left in secure software development practices.
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2021-31607
PUBLISHED: 2021-04-23
In SaltStack Salt 2016.9 through 3002.6, a command injection vulnerability exists in the snapper module that allows for local privilege escalation on a minion. The attack requires that a file is created with a pathname that is backed up by snapper, and that the master calls the snapper.diff function...
CVE-2021-31597
PUBLISHED: 2021-04-23
The xmlhttprequest-ssl package before 1.6.1 for Node.js disables SSL certificate validation by default, because rejectUnauthorized (when the property exists but is undefined) is considered to be false within the https.request function of Node.js. In other words, no certificate is ever rejected.
CVE-2021-2296
PUBLISHED: 2021-04-22
Vulnerability in the Oracle VM VirtualBox product of Oracle Virtualization (component: Core). The supported version that is affected is Prior to 6.1.20. Difficult to exploit vulnerability allows high privileged attacker with logon to the infrastructure where Oracle VM VirtualBox executes to compromi...
CVE-2021-2297
PUBLISHED: 2021-04-22
Vulnerability in the Oracle VM VirtualBox product of Oracle Virtualization (component: Core). The supported version that is affected is Prior to 6.1.20. Difficult to exploit vulnerability allows high privileged attacker with logon to the infrastructure where Oracle VM VirtualBox executes to compromi...
CVE-2021-2298
PUBLISHED: 2021-04-22
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.23 and prior. Easily exploitable vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attac...