Microsoft Windows HTML Help ActiveX Control Winhlp32.exe Item memory corruption

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

Summaryinfo

A vulnerability was found in Microsoft Windows. It has been classified as critical. This impacts an unknown function in the library HHCtrl.ocx of the file Winhlp32.exe of the component HTML Help ActiveX Control. This manipulation of the argument Item causes memory corruption. The identification of this vulnerability is CVE-2002-0823. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System) (unknown version). It has been declared as critical. Affected by this vulnerability is an unknown code block in the library HHCtrl.ocx of the file Winhlp32.exe of the component HTML Help ActiveX Control. The manipulation of the argument Item 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. The summary by CVE is:

Buffer overflow in Winhlp32.exe allows remote attackers to execute arbitrary code via an HTML document that calls the HTML Help ActiveX control (HHCtrl.ocx) with a long pathname in the Item parameter.

The bug was discovered 08/01/2002. The weakness was shared 04/02/2002 with Next Generation Security Software (Website). The advisory is shared at support.microsoft.com. This vulnerability is known as CVE-2002-0823. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details and also a public exploit are known.

After immediately, there has been an exploit disclosed. It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $25k-$100k.

Applying the patch 2000 SP3 is able to eliminate this problem. 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 2142.

The vulnerability is also documented in the databases at X-Force (9746), Exploit-DB (21485), SecurityFocus (BID 4857†), OSVDB (2991†) and Vulnerability Center (SBV-41007†). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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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

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
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Exploitinginfo

Class: Memory corruption
CWE: CWE-119
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: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍
Reliability: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Patch: 2000 SP3

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

Suricata ID: 2103148
Suricata Class: 🔍
Suricata Message: 🔍

TippingPoint: 🔍

McAfee IPS: 🔍
McAfee IPS Version: 🔍

SourceFire IPS: 🔍
PaloAlto IPS: 🔍

Timelineinfo

04/02/2002 🔍
04/02/2002 +0 days 🔍
05/27/2002 +55 days 🔍
05/27/2002 +0 days 🔍
08/01/2002 +66 days 🔍
08/12/2002 +11 days 🔍
12/14/2003 +488 days 🔍
08/13/2013 +3530 days 🔍
07/22/2014 +343 days 🔍
06/25/2025 +3991 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: support.microsoft.com
Organization: Next Generation Security Software
Status: Confirmed

CVE: CVE-2002-0823 (🔍)
GCVE (CVE): GCVE-0-2002-0823
GCVE (VulDB): GCVE-100-18709
X-Force: 9746
SecurityFocus: 4857 - Microsoft Windows WinHlp Item Buffer Overflow Vulnerability
OSVDB: 2991 - Microsoft WinHlp Active-X Item Parameter Overflow
Vulnerability Center: 41007 - Microsoft Windows 2000 Winhlp.exe Buffer Overflow Allows Remote Code Execution via a Crafted HTML Document, Critical

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

Entryinfo

Created: 07/23/2014 00:07
Updated: 06/25/2025 08:47
Changes: 07/23/2014 00:07 (79), 07/27/2019 15:44 (1), 06/25/2025 08:47 (20)
Complete: 🔍
Cache ID: 216::103

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