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.

ABTV //

DDoS detection

5/6/2019
12:35 PM
Larry Loeb
Larry Loeb
Larry Loeb
50%
50%

Quabot Trojan Evolves to Become Harder to Detect & Remove

Researchers at Cisco Talos were the first to find that Quabot Trojan has been updated and changed.

Qakbot, also known as Qbot, is a Trojan that has been seen since 2008. It tries to steal login credentials and eventually drain bank accounts. Qakbot has long utilized scheduled tasks to maintain persistence between bootups.

But Qakbot has changed its persistence mechanism in ways that can make it harder for users to detect and remove the trojan. Researchers at Cisco Talos were the first to find it has updated and changed this entire part of itself.

Qakbot now schedules tasks in the compromised systems to download the malware's binary which has been spread over multiple archives. This task will execute a JavaScript downloader that makes a binary request to multiple hijacked domains, getting the full binary after multiple requests.

As they put it, "Cisco Talos first observed a spike in requests to these hijacked domains on April 2, 2019. This coincides with DNS changes made to these domains on March 19, 2019."

The malware will then resemble itself on the compromised system, following it with a relaunch after each system restart so as to avoid removal.

Cisco sees that the way the malware sets itself up is the real story here. The rest of the attack remains Qakbot as far as it can be seen. The blog notes that, "The response… is obfuscated data that will be saved as (randalpha)_1.zzz and (randalpha)_2.zzz. The first 1,000 bytes of data are saved to the first .zzz file, while the remainder goes to the second file. The data in these files is decrypted with the code contained in the JavaScript downloader.… This code serves to reassemble the malicious Qakbot executable from the two .zzz files, using the type command. The two .zzz files are then deleted after the reassembled executable is run. The functionality of the Qakbot malware remains the same."

There's no question that there has been a change in the specific infection chain of Qakbot which can make it more difficult for a traditional anti-virus product to detect. An unaware av tool's result may allow this malware to be downloaded and slip past the guards. Threat detection that is focused only on seeing the full transfer of the malicious executable would likely miss this updated version of Qakbot as it whizzed past it. That means it is time to change the lists of IOC yet again for legacy AV products in a manner that will help detect this.

— Larry Loeb has written for many of the last century's major "dead tree" computer magazines, having been, among other things, a consulting editor for BYTE magazine and senior editor for the launch of WebWeek.

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
COVID-19: Latest Security News & Commentary
Dark Reading Staff 7/9/2020
Omdia Research Launches Page on Dark Reading
Tim Wilson, Editor in Chief, Dark Reading 7/9/2020
Mobile App Fraud Jumped in Q1 as Attackers Pivot from Browsers
Jai Vijayan, Contributing Writer,  7/10/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon
Current Issue
Special Report: Computing's New Normal, a Dark Reading Perspective
This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
Flash Poll
The Threat from the Internetand What Your Organization Can Do About It
The Threat from the Internetand What Your Organization Can Do About It
This report describes some of the latest attacks and threats emanating from the Internet, as well as advice and tips on how your organization can mitigate those threats before they affect your business. Download it today!
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-14174
PUBLISHED: 2020-07-13
Affected versions of Atlassian Jira Server and Data Center allow remote attackers to view titles of a private project via an Insecure Direct Object References (IDOR) vulnerability in the Administration Permission Helper. The affected versions are before version 7.13.6, from version 8.0.0 before 8.5....
CVE-2019-20901
PUBLISHED: 2020-07-13
The login.jsp resource in Jira before version 8.5.2, and from version 8.6.0 before version 8.6.1 allows remote attackers to redirect users to a different website which they may use as part of performing a phishing attack via an open redirect in the os_destination parameter.
CVE-2019-20898
PUBLISHED: 2020-07-13
Affected versions of Atlassian Jira Server and Data Center allow remote attackers to access sensitive information without being authenticated in the Global permissions screen. The affected versions are before version 8.8.0.
CVE-2019-20899
PUBLISHED: 2020-07-13
The Gadget API in Atlassian Jira Server and Data Center in affected versions allows remote attackers to make Jira unresponsive via repeated requests to a certain endpoint in the Gadget API. The affected versions are before version 8.5.4, and from version 8.6.0 before 8.6.1.
CVE-2019-20900
PUBLISHED: 2020-07-13
Affected versions of Atlassian Jira Server and Data Center allow remote attackers to inject arbitrary HTML or JavaScript via a cross site scripting (XSS) vulnerability in the Add Field module. The affected versions are before version 8.7.0.