Microsoft Releases Patch for Security Vulnerability
Microsoft has released a patch to fight what it deems an “extremely serious vulnerability” in IIS 5.0, its most recent Web server.
Microsoft has released a patch to fight what it
deems an “extremely serious vulnerability” in
IIS 5.0, its most recent Web server. The vulnerability,
if properly exploited, could give an attacker
complete control of a server. The attacker, with
control, could modify or destroy files and programs
and potentially the server itself. IIS 4.0 Web
servers aren’t affected.
It takes the form of a buffer-overrun
weakness. According to Microsoft, the vulnerability
results because the Internet Printing ISAPI extension
in Windows 2000 contains an unchecked buffer.
By sending a specially constructed request to
the extension, an attacker could cause code to
run in the Local System context.
The attacker could exploit the vulnerability
against any server with which he or she could
conduct a Web session. No other services need
to be available, and only port 80 (HTTP) or 443
(HTTPS) has to be open.
Find the patch at www.microsoft.com/Downloads/Release.asp?ReleaseID=29321.
Microsoft recommends that administrators take
immediate action to avoid this potential disaster.
The following are security updates
for Internet Explorer 5.01/5.5, Internet Information
Services 5.0 and Windows NT 4.0/2000:
- Internet Explorer Can
Divulge Location of Cached Content—A
vulnerability exists that lets a Web page or
HTML e-mail be used to ascertain the physical
location of cached content in Internet Explorer
5.01/5.5. An attacker exploiting this vulnerability
can open the cache, launch .chm files that contain
shortcuts to executables, and then run the executables.
For the patch that’ll eliminate this vulnerability,
go to www.microsoft.com/technet/security/bulletin/MS01-015.asp.
- Malformed WebDAV Request
Can Cause Internet Information Services 5.0
To Exhaust CPU Resources—WebDAV is an extension
of the HTTP protocol that allows remote authoring
and management of Web content. But a flaw exists
in the way WebDAV handles a certain type of
malformed request. If a stream of such requests
is directed at a server running Internet Information
Services 5.0, it can consume all of that server’s
CPU availability. For the patch that’ll eliminate
this vulnerability, go to www.microsoft.com/technet/security/bulletin/MS01-016.asp.
- Erroneous VeriSign-Issued
Digital Certificates Pose Spoofing Hazard—In
late January, an individual fraudulently claiming
to be a Microsoft employee applied for and received
two VeriSign Class 3 code-signing digital certificates.
These certificates can be used to make it appear
that certain programs, ActiveX controls, Office
macros and other executable content come from
Microsoft, when in fact they don’t. For more
information on this issue, go to www.microsoft.com/technet/security/bulletin/MS01-017.asp.
Microsoft, Redmond, Washington,