Apache/Lighthttpd/nginx Backdoor / Linux.Cdorked

Notification Type: IBM Security Protection Alert
Notification Date: May 15, 2013
Notification Version: 1.0
Name: Apache/Lighthttpd/nginx Backdoor / Linux.Cdorked
Public disclosure/
In the wild date:
April 26, 2013
Classification(s): Malware

Backdoors on Apache, Lighthttpd and nginx servers have been discovered in the wild which have been observed distributing links to the Blackhole exploit kit.

Researchers: Robert Freeman and Zubair Ashraf


ISS Coverage

Product Content Version
Proventia Network IDS
Proventia Network IPS
Proventia Network MFS
Proventia Server (Linux)
RealSecure Network
RealSecure Server Sensor
Proventia Desktop
Proventia Server IPS (Windows)
Propagation Techniques ISS Protection Available

Unauthorized Access Attempt

15 May 2013

* This signature is NOT blocked in the default policy.

Detailed Description

Business Impact:

The nature of the Cdorked backdoor permits a number of different malicious activities which can have business impact including data loss/theft and remote code execution. Moreover, it is being used to serve exploits to customers, internal users, and visitors to the website being served by the infected web server.

Affected Software:

Apache, Lighthttpd and nginx servers


It is not known what exploit vector is being used to gain access to the servers. There are multiple commands that the backdoor will accept and can be leveraged towards remote access, data theft and content manipulation. Moreover, infected webservers are also being used to very stealthily redirect visitors to malicious websites.



Revision History

1.0 Initial publication

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