Microsoft Internet Explorer 5.0.1/5.5 Dotless IP Address authentication spoofing

CVSS Meta Temp Score
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CTI Interest Score
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6.6$0-$5k0.00

Summaryinfo

A vulnerability has been found in Microsoft Internet Explorer 5.0.1/5.5 and classified as critical. The affected element is an unknown function of the component Dotless IP Address Handler. The manipulation leads to authentication spoofing. This vulnerability is listed as CVE-2001-0664. The attack may be initiated remotely. In addition, an exploit is available. Applying a patch is the recommended action to fix this issue. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Detailsinfo

A vulnerability was found in Microsoft Internet Explorer 5.0.1/5.5 (Web Browser) and classified as critical. This issue affects an unknown part of the component Dotless IP Address Handler. The manipulation with an unknown input leads to a authentication spoofing vulnerability. Using CWE to declare the problem leads to CWE-290. This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Internet Explorer 5.5 and 5.01 allows remote attackers to bypass security restrictions via malformed URLs that contain dotless IP addresses, which causes Internet Explorer to process the page in the Intranet Zone, which may have fewer security restrictions, aka the "Zone Spoofing vulnerability."

The issue has been introduced in 11/08/1999. The weakness was presented 10/10/2001 by Michiel Kikkert with Microsoft as MS01-051 as confirmed bulletin (Technet). The advisory is shared at microsoft.com. The identification of this vulnerability is CVE-2001-0664. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are unknown but a public exploit is available.

The exploit is available at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 702 days. During that time the estimated underground price was around $5k-$25k.

Applying the patch MS01-051 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 (7258), Exploit-DB (21118), SecurityFocus (BID 3420†), OSVDB (1971†) and Vulnerability Center (SBV-830†). See VDB-17574 for similar entry. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 6.6

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
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: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: MS01-051

Timelineinfo

11/08/1999 🔍
10/10/2001 +702 days 🔍
10/10/2001 +0 days 🔍
10/30/2001 +20 days 🔍
10/30/2001 +0 days 🔍
02/05/2003 +463 days 🔍
02/21/2003 +16 days 🔍
07/10/2014 +4156 days 🔍
03/23/2025 +3909 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: MS01-051
Researcher: Michiel Kikkert
Organization: Microsoft
Status: Confirmed

CVE: CVE-2001-0664 (🔍)
GCVE (CVE): GCVE-0-2001-0664
GCVE (VulDB): GCVE-100-17573
X-Force: 7258 - Microsoft Internet Explorer dotless IP could allow rendering of Web sites with incorrect Security Zone
SecurityFocus: 3420
OSVDB: 1971 - Microsoft IE Dotless IP Zone Spoofing
Vulnerability Center: 830 - [MS01-055] Microsoft Internet Explorer Zone Spoofing Vulnerability, Medium

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 07/10/2014 11:45 AM
Updated: 03/23/2025 07:23 AM
Changes: 07/10/2014 11:45 AM (71), 04/07/2017 12:06 PM (1), 03/23/2025 07:23 AM (25)
Complete: 🔍
Cache ID: 244:9D4:40

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