Date:  12.20.2000



Name:  Multiple Vulnerabilities in ZoneAlarm



Application:  ZoneAlarm 2.1.44



Platforms:  Windows 9x, ME, NT, 2000



Severity:  ZoneAlarm does not detect several types of common Nmap scans.

It is also possible for a remote attacker, under certain circumstances, to

gain complete access to the file system  and disable ZoneAlarm.



Author:  The WolfPak, alerts@wolfpak.dynip.com



ZoneAlarm (http://www.zonelabs.com) is marketed as a personal firewall and

threat detection/prevention tool. It is directed at the Windows-based home

user with a constant connection to the Internet with a DSL or Cable modem

service.



Unfortunately, ZoneAlarm does not allow its users to maintain a true

understanding of their threat level and exposure. Attackers scanning a

system employing ZoneAlarm will go unnoticed when using the common Nmap

scan types ACK, FIN, Xmas, Window & Null. While these scans do not return

lists of open ports to the attacker, the ZoneAlarm user is not aware of

the probe or the possibility of attacks being directed against them.



In addition, a window of opportunity exists during the boot process, which

allows a remote attacker access to shared resources available on the

ZoneAlarm protected device. If file sharing is enabled via Windows

Networking and proper Access Controls (ACL) are not utilized, complete

access to all shared resources can be obtained through simple NetBIOS

drive mapping (tools such as Legion have proven the existence and

viability of this threat). Attackers gaining access to the install

location of ZoneAlarm (C:\Program Files\Zone Labs\ZoneAlarm by default)

using such a share, it is possible for the attacker to disable ZoneAlarm

by deleting or renaming either the executable or its associated DLL files.

In an NTFS partition, the entire directory, and all associated files, are

installed with 'Everyone:Full Control' as permissions. The registry keys

created by ZoneAlarm (HKLM\Software\Zone Labs) also have weak permissions,

being set at 'Everyone:Special Access', including SetValue, CreateSubkey &

Delete. Note that users do receive a pop-up dialog window asking for the

location of the deleted or renamed file, however, the message is

sufficiently ambiguous to confuse most basic users into just clicking

CANCEL.



Once ZoneAlarm is disabled, complete unmitigated access to the file system

is obtained. Data  may be removed, copied, modified, deleted or otherwise

manipulated. From this point, normal remote code execution attacks can be

utilized to further compromise the system.



According to the manufacturer, "More than 8 million PC users have

downloaded ZoneAlarm", making it a very popular target indeed. Zone Labs

has been advised of these vulnerabilities and no patch or work around has

been provided.



ZoneAlarm is copyright Zone Labs, Inc.

WolfPak Homepage: http://wolfpak.dynip.com