Microsoft Windows NT 4.0/2000/XP HTML Help ActiveX Control hhctrl.ocx alink memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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8.8$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Microsoft Windows NT 4.0/2000/XP. Affected by this issue is the function alink of the file hhctrl.ocx of the component HTML Help ActiveX Control. Executing a manipulation can lead to memory corruption. This vulnerability is tracked as CVE-2002-0693. The attack can be launched remotely. Moreover, an exploit is present. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in Microsoft Windows NT 4.0/2000/XP (Operating System). It has been declared as critical. This vulnerability affects the function alink of the file hhctrl.ocx of the component HTML Help ActiveX Control. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Buffer overflow in the HTML Help ActiveX Control (hhctrl.ocx) in Microsoft Windows 98, 98 Second Edition, Millennium Edition, NT 4.0, NT 4.0 Terminal Server Edition, Windows 2000, and Windows XP allows remote attackers to execute code via (1) a long parameter to the Alink function, or (2) script containing a long argument to the showHelp function.

The weakness was disclosed 10/10/2002 by David Litchfield with Next Generation Security Software as MS02-055 as confirmed bulletin (Technet). The advisory is available at microsoft.com. This vulnerability was named CVE-2002-0693. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details and also a public exploit are known.

A public exploit has been developed in ANSI C. It is possible to download the exploit at securityfocus.com. It is declared as proof-of-concept. As 0-day the estimated underground price was around $100k and more. The vulnerability scanner Nessus provides a plugin with the ID 11147 (MS02-055: Unchecked Buffer in Windows Help Facility Could Enable Code Execution (323255)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows : Microsoft Bulletins and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 90167 (Windows Help Facility Remote Code Execution (MS02-055)).

Applying the patch MS02-055 is able to eliminate this problem. The bugfix is ready for download at microsoft.com. A possible mitigation has been published before and not just after the disclosure of the vulnerability. Attack attempts may be identified with Snort ID 3148. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 2667.

The vulnerability is also documented in the databases at X-Force (10253), Exploit-DB (21902), Tenable (11147), SecurityFocus (BID 5874†) and Vulnerability Center (SBV-1136†). The entry VDB-19043 is pretty similar. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Support

  • end of life (old version)

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.8
VulDB Meta Temp Score: 8.8

VulDB Base Score: 9.8
VulDB Temp Score: 8.8
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: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 11147
Nessus Name: MS02-055: Unchecked Buffer in Windows Help Facility Could Enable Code Execution (323255)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 11147
OpenVAS Name: Unchecked Buffer in Windows Help(Q323255)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: MS02-055

Snort ID: 3148
Snort Message: OS-WINDOWS Microsoft Windows HTML Help hhctrl.ocx clsid access attempt
Snort Class: 🔍
TippingPoint: 🔍
SourceFire IPS: 🔍
ISS Proventia IPS: 🔍

Timelineinfo

10/02/2002 🔍
10/03/2002 +1 days 🔍
10/10/2002 +7 days 🔍
10/10/2002 +0 days 🔍
10/10/2002 +0 days 🔍
10/24/2002 +14 days 🔍
04/29/2003 +187 days 🔍
07/30/2014 +4110 days 🔍
06/25/2025 +3983 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: MS02-055
Researcher: David Litchfield
Organization: Next Generation Security Software
Status: Confirmed

CVE: CVE-2002-0693 (🔍)
GCVE (CVE): GCVE-0-2002-0693
GCVE (VulDB): GCVE-100-19042

OVAL: 🔍

X-Force: 10253
SecurityFocus: 5874 - Microsoft Windows Help Facility ActiveX Control Buffer Overflow Vulnerability
Vulnerability Center: 1136 - [MS02-055] Unchecked Buffer in Windows Help, High

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

Entryinfo

Created: 07/30/2014 13:02
Updated: 06/25/2025 12:10
Changes: 07/30/2014 13:02 (81), 05/09/2019 18:45 (10), 12/30/2024 23:27 (16), 06/25/2025 12:10 (1)
Complete: 🔍
Cache ID: 216:55D:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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