| VID |
12007 |
| Severity |
40 |
| Port |
80, ... |
| Protocol |
TCP |
| Class |
WWW |
| Detailed Description |
The IIS web server has a buffer overflow vulnerability in chunked encoding transfer mechanism for ASP.
Chunked encoding is a means to transfer variable-sized units of data(called chunks) from a web client to a web server. Chunked encoding transfer mechanism is part of the ISAPI(Internet Services Application Programming Interface) extension that implements ASP. Before transferring data, a web client notifies the web server of "chunked" data's size, and then a web server allocates a buffer of the correct size. However, there is an arithmetic error in the way IIS calculates the size of a buffer used to hold a chunk. The result is that IIS allocated a buffer that is too small, allowing a remote attacker to overflow a buffer. Buffer used to store chunks are allocated on the heap, and therefore this vulnerability can be called a heap-based buffer overflow. This vulnerability allows a remote attacker to overflow a buffer and interrupt the ordinary operation of a IIS server or execute arbitrary code on the system with the privileges of ASP ISAPI extension, ASP.DLL.
* Platforms Affected:
Microsoft IIS 4.0
Microsoft IIS 5.0
Microsoft IIS 5.1
* References:
http://www.microsoft.com/technet/security/bulletin/ms02-018.asp
http://online.securityfocus.com/bid/4485 |
| Recommendation |
Apply the appropriate patch for your system
* Microsoft IIS 4.0(Windows NT 4.0 Workstation, Server, Enterprise Edition) :
1. Open the web page
http://www.microsoft.com/Downloads/Release.asp?ReleaseID=37931
2. Select your language from the drop-down list at the top of the page and click <Go>.
3. Click <Security Update>.
4. Download to your computer and Click it.
5. Restart your computer to complete the installation.
* Microsoft IIS 4.0(Windows NT 4.0 Server, Terminal Server Edition) :
1. Open the web page
http://www.microsoft.com/ntserver/terminalserver/downloads/critical/q317636/default.asp
2. Select your language from the drop-down list at the top of the page and click <Next>.
3. Click <Download Now>.
4. Download to your computer and Click it.
5. Restart your computer to complete the installation.
* Microsoft IIS 5.0 :
1. Open the web page
http://www.microsoft.com/Downloads/Release.asp?ReleaseID=37824
2. Select your language from the drop-down list at the top of the page and click <Go>.
3. Click <DOWNLOAD>.
4. Download to your computer and Click it.
* Microsoft IIS 5.1 :
1. Open the web page
http://www.microsoft.com/Downloads/Release.asp?ReleaseID=37857
2. Click <Download Now>.
4. Download to your computer and Click it.
* Cisco product running IIS :
Refer to Cisco Security Advisory site for affected products and update information.
http://www.cisco.com/warp/public/707/Microsoft-IIS-vulnerabilities-MS02-018.shtml |
| Related URL |
CVE-2002-0079 (CVE) |
| Related URL |
(SecurityFocus) |
| Related URL |
(ISS) |
|
