ENSRT Incident Note ETS-i-2005-12546
The Enterasys Networks 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 - W32.Elitper.E@mm
Release Date: 03/28/2005
Last Updated:
Overview
W32.Elitper.E@mm is a mass-mailing worm that retrieves addresses from the Windows Address Book on the infected computer and uses MAPI protocol to further proliferate the worm. Additionally, the worm attempts to proliferate through peer-to-peer file transfer.
Details below will describe the characteristics of the W32.Elitper.E@mm worm 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
The W32.Elitper.E@mm worm arrives via an e-mail attachment in the user's inbox with the following characteristics:
Subject Line: "Fwd: Microsoft SP2 Update"
Message Body: "Microsoft SP2 Update Urgent Download It"
File Attachment: "SP2 UPDATE.EXE"
If the infected file is executed on the host machine, the W32.Elitper.E@mm worm will infect the machine and begin the propagation process.
This process consists of the following actions:
1. The worm ends multiple processes and drops multiple copies of itself on the infected machine in the Program Files, System, and Windows directories.
2. The worm alters the system registry in order to ensure that the worm runs at Windows startup, and additionally disables multiple programs from being able to run.
3. The worm modifies, if available, a file that will cause the mIRC program to spread the worm other mIRC users.
4. The worm gathers addresses from the host computer's address book files and, using MAPI protocol, sends infected e-mails to the gathered addresses in an attempt at propagation.
5. Finally, the worm drops copies of itself in folders related to network and peer-to-peer sharing networks, in hopes of further propagation.
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.
Remediation
| Matrix N7 | X |
| Matrix E7 | X |
| Matrix E6 | X |
| Matrix E5 | X |
| Matrix E1 | X |
| VH | X |
| C-Series | X |
Detection
A specific Dragon signature to detect the W32.Elitper.E@mm worm can be retrieved via Dragon Live Update. It is located in the Master Library within the ENSRT category and named "ENSRT:W32-ELITPER-E-001".
The ENSRT:W32-ELITPER-E-001 signature, deployed on a Dragon NIDS sensor, can detect the worm as it egresses the Microsoft Exchange Server to external mail domains via the SMTP protocol.
NOTE: All signatures in the ENSRT library are disabled by default. These signatures must be enabled after they are imported into a custom library if they are to be successfully deployed.
Prevention
Trusted End System solutions are capable of monitoring various end system activity. TES is able to take immediate action such as firewalling specific IPs, TCP/UDP ports, applications, or placing the user into a Quarantine policy or VLAN until end system threat is mitigated. Learn more at: http://www.enterasys.com/solutions/secure-networks/trusted_end_system/
Containment
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. Once isolated, see your anti-virus vendor for Windows repair procedures for infected users.
References
http://securityresponse.symantec.com/avcenter/venc/data/w32.elitper.e@mm.html
http://www.trendmicro.com/vinfo/virusencyclo/default5.asp?VName=WORM%5FELITPER%2EE&VSect=T
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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:
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Version: 1.0 |
Date: 03/28/2005 |
Author: ENSRT STAFF |
Change |