NSFocus Security Advisory(SA2000-04) - A denial of service flaw has been found in the Microsoft Win9x netbios client. An attacker can modify his host file share service and perform DoS attack against a Win9x client that visits it. Windows 95, 98, and 98se are vulnerable.
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NSFOCUS Security Advisory(SA2000-04)
Topic£ºMicrosoft Win9x client driver type comparing vulnerability
Release Date£º August 20, 2000
Affected System:
================
- Microsoft Windows 95
- Microsoft Windows 98
- Microsoft Windows 98 Second Edition
Non-affected system£º
===================
- Microsoft Windows NT
- Microsoft Windows 2000
Impact:
=========
NSFOCUS security team has found a security flaw in Microsoft Win9x
NETBIOS client. Exploitation of this vulnerability, a malicious
attacker can modify his host file share service and perform DoS attack
to a Win9x client that visits it.
Description£º
============
When Win9x client accessing NETBIOS file shared services and comparing
the driver types, if the returned type from server is none of
below:"£¿£¿£¿£¿£¿"," A£º"," LPT1£º"," COMM"or"IPC"£¬it will lead to
the sixth result, which is fake cause there are only five of them. So,
win9x client will get a wrong driver pointer from conversion, transfer
the control to the wrong driver function address and finally crash.
Workaround:
====================
Don't access the untrusted host's file share service.
Microsoft has been informed.
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==========
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