Microsoft Issues Security Patches:
"Hardest hit in this month's batch of patches is IE, which contains five newly discovered vulnerabilities. Three of the flaws are related to the cross-domain security model in the browser. This mechanism is meant to prevent windows in different domains from sharing information. However, these weaknesses allow an attacker to run script in the browser's My Computer zone, which typically does not carry the same level of security as the Internet zone might."

In order to exploit this flaw, the attacker would either need to entice the user into visiting a malicious Web site or opening an HTML mail message containing the attack code. This would let the attacker access data from other Web sites that the user has visited and read files on the user's machine, Microsoft said in its bulletin.

Another flaw in IE concerns the manner in which the browser passes zone data to XML objects. Like the other three vulnerabilities, this one also can be exploited via Web sites and HTML mail messages. However, the attack also requires that users agree to download an HTML file, which would let the attacker read local files on the user's machine, if he knows the exact location of the files.

The final weakness in IE affects drag-and-drop operations during dynamic HTML events. If a user clicked on a link supplied by an attacker, the attacker could save a file on a user's machine in an arbitrary location. All of these flaws affect IE 5.01, 5.5 and 6, including IE 6, Service Pack 1.

The batch of patches also addresses a buffer overrun flaw in Windows 2000 and XP that could allow an attacker to run arbitrary code on remote machines. The vulnerability is in the Workstation service in Windows and a successful exploitation would give the attacker complete control of the compromised PC, Microsoft said.

Windows XP users who have installed the patch for MS03-043 are already protected against this vulnerability, but all Windows 2000 users would still need to apply this latest patch.…

The patches are at Microsoft's Security and Privacy Page.
http://www.microsoft.com/security/

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