ISS Security Brief: Vulnerability in SMB Parsing in ISS Products

From: X-Force (
Date: 02/26/04

Date: Thu, 26 Feb 2004 13:39:44 -0500 (EST)


Internet Security Systems Security Brief
February 26, 2004

Vulnerability in SMB Parsing in ISS Products


A vulnerability was discovered in the SMB (Server Message Block) protocol
parsing routines of the ISS Protocol Analysis Module (PAM) component found
in some ISS products. The flaw relates to incorrect parsing of the SMB
protocol, which may lead to a heap overflow condition.

Affected Versions:

RealSecure Network 7.0, XPU 20.15 through 22.9
Real Secure Server Sensor 7.0 XPU 20.16 through 22.9
Proventia A Series XPU 20.15 through 22.9
Proventia G Series XPU 22.3 through 22.9
Proventia M Series XPU 1.3 through 1.7
RealSecure Desktop 7.0 eba through ebh
RealSecure Desktop 3.6 ebr through ecb
RealSecure Guard 3.6 ebr through ecb
RealSecure Sentry 3.6 ebr through ecb
BlackICE PC Protection 3.6 cbr through ccb
BlackICE Server Protection 3.6 cbr through ccb

All updates are available from the ISS Download Center:


The vulnerability is caused by incorrect parsing of SMB information. The
flaw may be exploited due to insufficient size checks of certain protocol
fields. ISS X-Force believes that exploitation of this issue is possible.
In order to cause memory corruption, it is necessary to establish a
legitimate SMB connection to a server. This may be a mitigating factor in
many network configurations. Externally facing networks that do not allow
SMB connections are not vulnerable to attack.

For complete ISS X-Force Security Alert, please visit:


About Internet Security Systems (ISS)
Founded in 1994, Internet Security Systems (ISS) (Nasdaq: ISSX) is a
pioneer and world leader in software and services that protect critical
online resources from an ever-changing spectrum of threats and misuse.
Internet Security Systems is headquartered in Atlanta, GA, with
additional operations throughout the Americas, Asia, Australia, Europe
and the Middle East.

Copyright (c) 2003 Internet Security Systems, Inc. All rights reserved

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