ENSRT Incident Note ETS-i-2005-12561
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.Kedebe@mm
Release Date: 04/25/2005
Last Updated:
Overview
The W32.Kedebe@mm worm propagates by sending copies of itself via an e-mail with an embedded SMTP engine. Furthermore, system security is threatened by the deletion of security related files and prevention of Internet access to security sites.
Details below describe the characteristics of the W32.Kedebe@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.Kedebe@mm worm arrives on the user's PC via an e-mail with an enclosed attachment. If the attachment is executed, the Microsoft Windows PC will become infected.
The mail message contains one of the following Subject lines:
- Mail server upgrading info.
- Attention! Your Internet account has been...
- Don't send this to me again!
- I'm still waiting for your reply...
- Attention!
- Internet Explorer 7.0 on the row!!
- Urgent! Symantec Security Response.
- I have received your mail.
- Sign a petition for Micael Jackson
The e-mail contains a CAB attachment with an embedded executable. The attachment has one of the following names:
- MyPicture
- replied
- BinaryFormat
- MicrosoftIE7.0Documentation
- Patch
- YourMail
- TempAccountInfo
- NeedHelp
Once the worm has been executed the following actions are taken against the infected PC.
1) Deletes executables from directories containing security related software.
2) Updates registry entries to restart the worm at Windows system start.
3) Changes the host file to prevent Internet access to security related WEB sites.
4) Displays the following error message when the worm is first executed:
"Error: 4047
Invalid procedure call at this time.
Press OK to terminate."
5) Gathers e-mail addresses from files on the infected PC to aid further proliferation.
6) Attempts to update the worm by downloading new variants from the Internet.
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
Specific Dragon signatures that detect the W32.Kedebe@mm worm can be retrieved via Dragon Live Update and are located in the Master Library within the ENSRT category. The nine signatures with the prefix "ENSRT: W32-KEDEBE" can be copied into a custom library and deployed on a Dragon network sensor that is protecting the enterprise SMTP server to detect end-user class machines which have become infected with the worm.
If utilizing Dynamic Intrusion Response (DIR), a Dragon Alarmtool policy that consists of an event group that contains all of the signatures within the "ENSRT:W32-KEDEBE" family should be used. A threshold parameter of at least three signature detections within a time span of 60 seconds should be used to mitigate the existence of false positives.
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
The Enterasys Dynamic Intrusion Response (DIR) solution can be utilized to 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 placed in a quarantine VLAN. Once isolated, see your anti-virus vendor for Windows repair procedures for infected users.
References
http://securityresponse.symantec.com/avcenter/venc/data/w32.kedebe@mm.html
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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: 04/25/2005 |
Author: ENSRT STAFF |
Change |