Severity: High
14 October, 2008
Summary:
§ This vulnerability affects: Internet Explorer 7 and earlier versions
§ How an attacker exploits it: By enticing one of your users to visit a malicious Web page or link
§ Impact: In the worst case, the attacker can execute code on your user’s computer, gaining complete control of it
§ What to do: Deploy the appropriate Internet Explorer patches immediately
Severity: High
14 October, 2008
Summary:
§ This vulnerability affects: Internet Explorer 7 and earlier versions
§ How an attacker exploits it: By enticing one of your users to visit a malicious Web page or link
§ Impact: In the worst case, the attacker can execute code on your user’s computer, gaining complete control of it
§ What to do: Deploy the appropriate Internet Explorer patches immediately
Exposure:
In a security bulletin released today as part of its monthly patch update, Microsoft describes six vulnerabilities in Internet Explorer (IE) versions 5.01, 6.0, and 7.0. The two worst vulnerabilities involve memory corruption issues. While they differ technically, they have the same scope and impact. By luring one of your users into visiting a maliciously crafted Web page, an attacker can exploit either memory corruption vulnerability to execute code on that user’s computer, inheriting that user’s privileges. Typically, Windows users have local administrative privileges; in that case, the attacker could gain complete control of the victim’s computer.
Microsoft describes the remaining four vulnerabilities as “cross-domain information disclosure” vulnerabilities. Most web browsers impose a security measure called the same origin policy to help prevent one web site from accessing the contents of another web site. This security measure should protect you from an entire range of cross-site or cross-domain attacks, such as cross-site scripting (XSS) attacks. Unfortunately, IE suffers from four cross-domain information disclosure flaws that would allow attackers to bypass the same origin policy. Though technically different, an attacker would leverage all four flaws in the same way: By enticing one of your users into following a specially crafted link, an attacker could exploit these vulnerabilities to execute scripts under the context of a legitimate site. The attacker could leverage this capability to read data from the legitimate site. For instance, if your users visit secure web sites which store sensitive data, an attacker might leverage this flaw to steal that sensitive data.
In addition to fixing these six newly announced flaws, today’s Internet Explorer patch also fixes all previously known flaws.
Solution Path:
These patches fix serious issues. You should download, test, and deploy the appropriate IE patches as soon as possible.
§ Internet Explorer 6.0
§ Microsoft no longer supports 98, ME, or XP SP1.
§ For Windows Server 2003 Itanium
§ Internet Explorer 7.0
§ For Windows Server 2003 Itanium
§ For Windows Server 2008 Itanium
For All WatchGuard Users:
These attacks travel as normal-looking HTTP traffic, which you must allow if your network users need to access the World Wide Web. Therefore, the patches above are your best solution.
Status:
Microsoft has released patches to fix these vulnerabilities.