BID:3190

Microsoft IIS SSI Buffer Overrun Privelege Elevation Vulnerability

Info

Microsoft IIS SSI Buffer Overrun Privelege Elevation Vulnerability

Bugtraq ID:	3190
Class:	Boundary Condition Error
CVE:
Remote:	No
Local:	Yes
Published:	Aug 15 2001 12:00AM
Updated:	Aug 15 2001 12:00AM
Credit:	This vulnerability was reported by the NSFocus Security Team.
Vulnerable:	Microsoft Windows NT Workstation 4.0 SP6a Microsoft Windows NT Workstation 4.0 SP6 Microsoft Windows NT Workstation 4.0 SP5 Microsoft Windows NT Workstation 4.0 SP4 Microsoft Windows NT Workstation 4.0 SP3 Microsoft Windows NT Workstation 4.0 SP2 Microsoft Windows NT Workstation 4.0 SP1 Microsoft Windows NT Workstation 4.0 Microsoft Windows NT Terminal Server 4.0 SP6 Microsoft Windows NT Terminal Server 4.0 SP5 Microsoft Windows NT Terminal Server 4.0 SP4 Microsoft Windows NT Terminal Server 4.0 SP3 Microsoft Windows NT Terminal Server 4.0 SP2 Microsoft Windows NT Terminal Server 4.0 SP1 Microsoft Windows NT Terminal Server 4.0 Microsoft Windows NT Server 4.0 SP6a + Avaya DefinityOne Media Servers + Avaya DefinityOne Media Servers + Avaya IP600 Media Servers + Avaya IP600 Media Servers + Avaya S3400 Message Application Server 0 + Avaya S8100 Media Servers 0 + Avaya S8100 Media Servers 0 Microsoft Windows NT Server 4.0 SP6 Microsoft Windows NT Server 4.0 SP5 Microsoft Windows NT Server 4.0 SP4 Microsoft Windows NT Server 4.0 SP3 Microsoft Windows NT Server 4.0 SP2 Microsoft Windows NT Server 4.0 SP1 Microsoft Windows NT Server 4.0 Microsoft Windows NT Enterprise Server 4.0 SP6a Microsoft Windows NT Enterprise Server 4.0 SP6 Microsoft Windows NT Enterprise Server 4.0 SP5 Microsoft Windows NT Enterprise Server 4.0 SP4 Microsoft Windows NT Enterprise Server 4.0 SP3 Microsoft Windows NT Enterprise Server 4.0 SP2 Microsoft Windows NT Enterprise Server 4.0 SP1 Microsoft Windows NT Enterprise Server 4.0 Microsoft Windows 2000 Server SP2 Microsoft Windows 2000 Server SP1 Microsoft Windows 2000 Server + Avaya DefinityOne Media Servers + Avaya IP600 Media Servers + Avaya S3400 Message Application Server 0 + Avaya S8100 Media Servers 0 Microsoft Windows 2000 Professional SP2 Microsoft Windows 2000 Professional SP1 Microsoft Windows 2000 Professional Microsoft Windows 2000 Datacenter Server SP2 Microsoft Windows 2000 Datacenter Server SP1 Microsoft Windows 2000 Datacenter Server Microsoft Windows 2000 Advanced Server SP2 Microsoft Windows 2000 Advanced Server SP1 Microsoft Windows 2000 Advanced Server

Not Vulnerable:	Microsoft Windows 2000 Server SP3 Microsoft Windows 2000 Professional SP3 Microsoft Windows 2000 Datacenter Server SP3 Microsoft Windows 2000 Advanced Server SP3

Discussion

Microsoft IIS SSI Buffer Overrun Privelege Elevation Vulnerability

A vulnerability exists in Microsoft IIS 4.0 and 5.0 that could allow a user with permission to write content to the IIS server to run any code in Local System context.

Exploit / POC

Microsoft IIS SSI Buffer Overrun Privelege Elevation Vulnerability

The following is an exploit provided by NSFocus:

1. Create a file "test.shtml" with following file content:



Number of 'A' should be over 2049.

2. Create a directory "a" under Web directory.
Copy "test.shtml" to "a" directory.

3. Request "test.shtml" through web browser:
http://webhost/a/test.shtml

4. IIS would return a blank page which indicates that an overflow has occurred.
Meanwhile the trailing '\0' has overwritten the last byte of saved EBP.

On the contrary, in case that the contained file has a shorter name like
'AA', IIS would return a SSI file '/a/AA' error message when receiving
the request.

Additionally, a remote shell exploit 'jim.c' has been made available by Indigo <[email protected]>.

/data/vulnerabilities/exploits/jim.c

Solution / Fix

Microsoft IIS SSI Buffer Overrun Privelege Elevation Vulnerability

Solution:
Microsoft has released patches which resolves this issue:

Microsoft Windows 2000 Server SP2