Microsoft Windows NT 4.0 TCP Initial Sequence Number authentication spoofing

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Microsoft Windows NT 4.0. Impacted is an unknown function of the component TCP Initial Sequence Number Handler. Executing a manipulation can lead to authentication spoofing. This vulnerability is registered as CVE-2000-0328. No exploit is available. This vulnerability has a historic impact due to its background and reception. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability has been found in Microsoft Windows NT 4.0 (Operating System) and classified as critical. This vulnerability affects some unknown functionality of the component TCP Initial Sequence Number Handler. The manipulation with an unknown input leads to a authentication spoofing vulnerability. The CWE definition for the vulnerability is CWE-290. This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. As an impact it is known to affect confidentiality. CVE summarizes:

Windows NT 4.0 generates predictable random TCP initial sequence numbers (ISN), which allows remote attackers to perform spoofing and session hijacking.

The weakness was published 08/24/1999 as MS99-046 as confirmed bulletin (Technet). The advisory is shared for download at microsoft.com. This vulnerability was named CVE-2000-0328. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 04/19/2026). This vulnerability has a historic impact due to its background and reception.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 82005 (Predictable TCP Initial Sequence Numbers Vulnerability).

Applying the patch MS99-046 is able to eliminate this problem. The bugfix is ready for download at microsoft.com.

The vulnerability is also documented in the databases at X-Force (3168), SecurityFocus (BID 604†) and Vulnerability Center (SBV-39818†). Similar entries are available at VDB-13695, VDB-16127 and VDB-16830. VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Authentication spoofing
CWE: CWE-290 / CWE-287
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: MS99-046

Timelineinfo

01/01/1995 🔍
08/24/1999 +1696 days 🔍
08/24/1999 +0 days 🔍
08/24/1999 +0 days 🔍
06/03/2013 +5032 days 🔍
06/21/2014 +383 days 🔍
04/19/2026 +4320 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: MS99-046
Status: Confirmed

CVE: CVE-2000-0328 (🔍)
GCVE (CVE): GCVE-0-2000-0328
GCVE (VulDB): GCVE-100-14800
X-Force: 3168
SecurityFocus: 604 - NT Predictable TCP Sequence Number Vulnerability
Vulnerability Center: 39818 - [MS99-046] Windows NT Predictable TCP Sequence Number Allows Session Hijacking, Medium

See also: 🔍

Entryinfo

Created: 06/21/2014 21:34
Updated: 04/19/2026 10:50
Changes: 06/21/2014 21:34 (44), 05/01/2017 11:31 (22), 04/19/2026 10:50 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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