Attacks/Breaches
12/19/2012
04:40 PM
Connect Directly
Google+
Twitter
RSS
E-Mail
50%
50%

New Apache Server Attack Discovered

Exploit ultimately leads to theft of online banking credentials via Zeus variant

One of the most popular Web server platforms is now serving up malware in an attack that ultimately aims to steal online banking credentials.

A new Apache exploit discovered and analyzed by Eset injects malware into Web pages on a Web server. The so-called Linux/Chapro.A variant has multiple features to camouflage its presence, and basically "tricks" the unsuspecting Apache software into infecting a visitor's machine, according to Eset's findings.

The malware injects an iFrame onto the server that ultimately leads to the installation of Zeus variant Win32/Zbot. It also links to the so-called Sweet Orange exploit kit landing page, out of Lithuania.

"More than half of all web servers on the Internet use Apache, so when we discovered a malicious Apache module in the wild last month, being used to inject malicious content into web pages displayed by compromised web servers, we were understandably concerned," says Pierre-Marc Bureau, security intelligence program manager at Eset, in a blog posting on the malware.

Linux/Chapro.A injects iFrames by sending an HTTP POST request to its command-and-control server every 10 minutes.

The malware pushes a pop-up message to the banking customer asking for a bank card CVV code: If the user falls for it and provides it, that information as well as banking credentials go to the bad guys.

Just how it all starts is still unclear. "This is a malicious module installed on an otherwise non-malicious server. This implies the controls protecting server access were circumvented or there is an insider involved. However, we also need to consider the module could have been part of a corrupted Linux distribution or application package," Bureau told Dark Reading.

He says Eset doesn't know how the module got onto the server to begin with: "Could be a weak password, vulnerable Web application, etc. The user needs high privileges to load the module so, he most probably had root on the machine," Bureau says.

"We don't know who is spreading this but probably a gang specializing in such attacks, then renting 'traffic' to other groups," he says.

The attack employs multiple stealth modes to mask it from website operators, including checking for known bots and active SSH systems. "If a visitor browses a page using any of the same IPs involved in a SSH connection, it will not be served the malicious content. This helps hide the malicious content from system administrators, Web developers, and others who might be working on the Web server," Bureau says.

Linux/Chapro.A also places a cookie in the visitor's browser before the malware injects the iFrame into the Web content. "Malicious content will not be served if the visiting browser already had that cookie set. This helps ensure that visitors will not receive malicious content over and over again, making it more difficult to determine how a system was infected," he says. And the malware ensures that it only infects a victim once by keeping a list of IP addresses it has infected.

The malware's command-and-control server was hosted in Germany, but since has gone offline.

"This complicated case spreads across three different countries, targeting users from a fourth one, making it very hard for law enforcement agencies to investigate and mitigate," Bureau blogged. "It is not clear at this point in time if the same group of people are behind the whole operation, or if multiple gangs collaborated, perhaps with one to drive traffic to the exploit pack and sell the infected computers to another gang operating a botnet based on Win32/Zbot."

The full Eset blog post is here.

Have a comment on this story? Please click "Add Your Comment" below. If you'd like to contact Dark Reading's editors directly, send us a message.

Kelly Jackson Higgins is Executive Editor at DarkReading.com. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise ... View Full Bio

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2010-5110
Published: 2014-08-29
DCTStream.cc in Poppler before 0.13.3 allows remote attackers to cause a denial of service (crash) via a crafted PDF file.

CVE-2012-1503
Published: 2014-08-29
Cross-site scripting (XSS) vulnerability in Six Apart (formerly Six Apart KK) Movable Type (MT) Pro 5.13 allows remote attackers to inject arbitrary web script or HTML via the comment section.

CVE-2013-5467
Published: 2014-08-29
Monitoring Agent for UNIX Logs 6.2.0 through FP03, 6.2.1 through FP04, 6.2.2 through FP09, and 6.2.3 through FP04 and Monitoring Server (ms) and Shared Libraries (ax) 6.2.0 through FP03, 6.2.1 through FP04, 6.2.2 through FP08, 6.2.3 through FP01, and 6.3.0 through FP01 in IBM Tivoli Monitoring (ITM)...

CVE-2014-0600
Published: 2014-08-29
FileUploadServlet in the Administration service in Novell GroupWise 2014 before SP1 allows remote attackers to read or write to arbitrary files via the poLibMaintenanceFileSave parameter, aka ZDI-CAN-2287.

CVE-2014-0888
Published: 2014-08-29
IBM Worklight Foundation 5.x and 6.x before 6.2.0.0, as used in Worklight and Mobile Foundation, allows remote authenticated users to bypass the application-authenticity feature via unspecified vectors.

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
This episode of Dark Reading Radio looks at infosec security from the big enterprise POV with interviews featuring Ron Plesco, Cyber Investigations, Intelligence & Analytics at KPMG; and Chris Inglis & Chris Bell of Securonix.