ENSRT Incident Note ETS-i-2006-12598
The Enterasys Security Response Team (ENSRT) publishes incident notes to provide information for our constituents to raise awareness of issues deemed threatening to the security and integrity of our customers.
Worm - WORM_SOBER.AG
Release Date: 11/28/2005
Last Updated: 01/05/2006
Overview
WORM_SOBER.AG spreads via SMTP utilizing addresses gathered from the infected computer. The worm overwrites files and causes system instability.
Details below describe the characteristics of WORM_SOBER.AG as well as provide detection, containment, and prevention techniques available through Enterasys Secure Networks solutions.
Systems affected
Windows operating systemsSystems not affected
Linux and MAC/OSXDescription
WORM_SOBER.AG arrives via an e-mail from a spoofed sender address. The messages contained within the e-mails will be one of the following:
E-MAIL #1
Subject:
• Registration Confirmation
• Your Password
Message body:
• Account and Password Information are attached!
• Protected message is attached!
followed by one of these strings:
***** Go to: http://www. target domain
***** Email: postman@ target domain
Attachment:
• reg_pass.zip
• reg_pass-data.zip
E-MAIL #2
Subject:
• Mail delivery failed
• smtp mail failed
Message body:
This is an automatically generated Delivery Status Notification.
SMTP_Error []
I'm afraid I wasn't able to deliver your message.
This is a permanent error; I've given up. Sorry it didn't work out.
The full mail-text and header is attached!
Attachment:
• mail.zip
• mail_body.zip
E-MAIL#3
Subject: hi,_ive_a_new_mail_address
Message body:
hey its me, my old address dont work at time. i dont know why?!
in the last days ive got some mails. i' think thaz your mails but im not sure!
plz read and check ...
cyaaaaaaa
Attachment: mailtext.zip
E-MAIL#4
From:
• sender @fbi.gov
• sender @cia.gov
senderwill be any of the following:
• Admin
• Department
• Mail
• Office
• Post
E-MAIL #5
Subject:
• You visit illegal websites
• Your IP was logged
Message body:
Dear Sir/Madam,
we have logged your IP-address on more than 30 illegal Websites.
Important:
Please answer our questions!
The list of questions are attached.
Yours faithfully,
Steven Allison
followed by any of the following strings:
• *** Federal Bureau of Investigation -FBI-
*** 935 Pennsylvania Avenue, NW, Room 3220
*** Washington, DC 20535
*** phone: (202) 324-3000
• ++++ Central Intelligence Agency -CIA-
++++ Office of Public Affairs
++++ Washington, D.C. 20505
++++ phone: (703) 482-0623
++++ 7:00 a.m. to 5:00 p.m., US Eastern time
Attachment:
• list.zip
• question_list.zip
E-MAIL #6
Subject: Paris Hilton & Nicole Richie
Message body:
The Simple Life:
View Paris Hilton & Nicole Richie video clips , pictures & more ;)
Download is free until Jan, 2006!
Please use our Download manager.
Attachment: downloadm.zip
In addition there are several more variations that utilze similar e-mails written in German.
If the attachment is executed, the following actions are taken against the conquered PC.
1. The worm displays a false error message in order to convince the user that the file did not properly execute.
2. Creates a file called WinSecurity and drops several copies of itself in there using various names. It also leaves other files in various locations. These files are used store information gathered by the worm such as the email addresses it harvests from the affected system.
3. The worm alters the system's registry entries so that the worm will execute upon each system boot.
4. The worm terminates specific Windows processes in an attempt to make the system more vulnerable to malicious attacks.
5. Starting on January 6th, 2006, this "SOBER" worm will begin to connect to certain WEB sites to download additional worm components.
The list of internet sites that could be contacted include:
free.pages.at
home.arcor.de
home.pages.at
people.freenet.de
scifi.pages.at
Threat Assessment
Mass-mailing worms if not addressed through prudent remediation steps may congest mail servers and/or degrade network performance. Mass-mailing worms may impact individual system performance and compromise security settings allowing unauthorized remote access to the compromised host.
Trojans or backdoor listeners if not addressed through prudent remediation steps, can compromise network and host security. Additionally, trojans and backdoor listeners potentially allow theft of information, unauthorized remote access, and damage to critical files.
Remediation
| Matrix N-Series | X |
| Matrix E7 | X |
| Matrix E6 | X |
| Matrix E5 | X |
| Matrix E1 | X |
| VH | X |
| C-Series | X | B-Series | X |
Detection
Specific Dragon signatures to detect WORM_SOBER.AG can be retrieved via Dragon Live Update and are located in the Master Library within the ENSRT category. The seven signatures with the prefix "ENSRT:WORM-SOBER-AG" can be copied into a custom library and deployed on Dragon network sensors to successfully detect end-user class machines which have become infected with the worm.
As of January 5th, 2006, ENSRT has released an additional five Dragon signatures to detect the time based download of additional worm components. Please note the Dragon signatures 008 through 012 with the signature prefix of "ENSRT:WORM-SOBER-AG" can be added to the existing signature library to detect the January 6th sequenced download. Additionally, if the Internet domains referenced in the description section of this advisory are commonly accessed by the enterprise community false positive signature events could occur.
Prevention
Enterasys offers two forms of prevention:
1) The Enterasys Sentinel ™ solution is capable of monitoring various end system activities. Enterasys Sentinel ™ is able to take immediate action such as traffic filtering for IP addresses and TCP/UDP ports or placing the user into a Quarantine policy or VLAN until end system threat is mitigated.
2) In-line attack disruption can be achieved via the Dragon Intrusion Prevention System (IPS) to drop detected events before vulnerabilities can be exploited.
Containment
The Enterasys Secure Networks ™ solution can remove infected end-users from the enterprise network by detecting the infection with a Dragon NIDS signature (see "Detection" section of this report), locating the user's connection point using Automated Security Manager's location services module, and either placing the user in a quarantine VLAN or disabling the associated switch port for the user.
Using Enterasys Policy Manager, enforce a policy that allows SMTP traffic from end user PCs to authorized SMTP mail servers and blocks SMTP traffic to unauthorized end users or unknown Internet systems. If the SMTP protocol is not implemented for end users within the enterprise, consider implementing a policy blocking SMTP traffic from end user ports.
Repair
Monitor Dragon RealTime Console for alerts that end-user PCs have become infected with the virus. If utilizing the DIR solution, users can either be expunged from the network or provided a quarantine policy. Once isolated, see your anti-virus vendor for Windows repair procedures for infected users.
References
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=WORM%5FSOBER%2EAG&VSect=P
This document and the information contained herein are intended solely for informational use. Enterasys Networks, Inc. makes no representations or warranties of any kind, whether expressed or implied, with respect to this information and assumes no responsibility for its accuracy or completeness. Enterasys Networks, Inc. hereby disclaims all liability and warranty for any information contained herein and all the material and information herein exists to be used only on an "as is" basis. More specific information may be available on request. By your review and/or use of the information contained herein, you expressly release Enterasys from any and all liability related in any way to this information.
A copy of the text of this section is an uncontrolled copy, and may lack important information or contain factual errors. All information herein is Copyright ©Enterasys Networks, Inc. All rights reserved. All information above is subject to change without notice.
Revision History:
|
Version: 1.0 |
Date: 11/28/2005 |
Author: ENSRT STAFF |
Change |