Microsoft Windows 2000/Server 2003/XP HTML Help Input heap-based overflow

CVSS Meta Temp Score
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5.9$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Microsoft Windows 2000/Server 2003/XP. Impacted is an unknown function of the component HTML Help Input Handler. This manipulation causes heap-based overflow. This vulnerability is tracked as CVE-2005-1208. The attack is possible to be carried out remotely. No exploit exists. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability classified as critical was found in Microsoft Windows 2000/Server 2003/XP (Operating System). Affected by this vulnerability is some unknown processing of the component HTML Help Input Handler. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect confidentiality, and integrity. The summary by CVE is:

Integer overflow in Microsoft Windows 98, 2000, XP SP2 and earlier, and Server 2003 SP1 and earlier allows remote attackers to execute arbitrary code via a crafted compiled Help (.CHM) file with a large size field that triggers a heap-based buffer overflow, as demonstrated using a "ms-its:" URL in Internet Explorer.

The bug was discovered 03/16/2005. The weakness was disclosed 06/14/2005 by Peter Winter-Smith (DiGiT) with eEye Digital Security as MS05-026 (Website). It is possible to read the advisory at microsoft.com. This vulnerability is known as CVE-2005-1208 since 04/22/2005. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 1944 days. During that time the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 18482 (MS05-026: Vulnerability in HTML Help Could Allow Remote Code Execution (896358)), 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 90253 (Microsoft HTML Help Remote Code Execution Vulnerability (MS05-026)).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at microsoft.com. A possible mitigation has been published immediately after the disclosure of the vulnerability. Attack attempts may be identified with Snort ID 3821. In this case the pattern text/plain is used for detection. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 3554.

The vulnerability is also documented in the databases at X-Force (20825), Tenable (18482), SecurityFocus (BID 13953†), OSVDB (17305†) and Secunia (SA15683†). Additional details are provided at kb.cert.org. The entries VDB-1570, VDB-1569 and VDB-1568 are pretty similar. Be aware that VulDB is the high quality source for vulnerability data.

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: 6.5
VulDB Meta Temp Score: 5.9

VulDB Base Score: 6.5
VulDB Temp Score: 5.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Proof-of-Concept

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 18482
Nessus Name: MS05-026: Vulnerability in HTML Help Could Allow Remote Code Execution (896358)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: microsoft.com

Snort ID: 3821
Snort Message: WEB-CLIENT CHM file transfer attempt
Snort Pattern: 🔍
TippingPoint: 🔍

McAfee IPS: 🔍
McAfee IPS Version: 🔍

SourceFire IPS: 🔍
ISS Proventia IPS: 🔍
Fortigate IPS: 🔍

Timelineinfo

02/17/2000 🔍
03/16/2005 +1854 days 🔍
04/22/2005 +37 days 🔍
06/14/2005 +53 days 🔍
06/14/2005 +0 days 🔍
06/14/2005 +0 days 🔍
06/14/2005 +0 days 🔍
06/14/2005 +0 days 🔍
06/14/2005 +0 days 🔍
06/14/2005 +0 days 🔍
06/14/2005 +0 days 🔍
06/15/2005 +0 days 🔍
06/17/2005 +2 days 🔍
07/04/2025 +7322 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: MS05-026
Researcher: Peter Winter-Smith (DiGiT)
Organization: eEye Digital Security
Status: Confirmed

CVE: CVE-2005-1208 (🔍)
GCVE (CVE): GCVE-0-2005-1208
GCVE (VulDB): GCVE-100-1567

OVAL: 🔍

CERT: 🔍
X-Force: 20825
SecurityFocus: 13953 - Microsoft Windows HTML Help Remote Code Execution Vulnerability
Secunia: 15683 - Microsoft Windows HTML Help Input Validation Vulnerability, Highly Critical
OSVDB: 17305 - Microsoft Windows HTML Help (CHM) File Overflow
SecurityTracker: 1014195
Vulnerability Center: 8324 - [MS05-026] Remote Code Execution in Microsoft Windows via HTML Help, Medium

Misc.: 🔍
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Entryinfo

Created: 06/17/2005 17:46
Updated: 07/04/2025 17:24
Changes: 06/17/2005 17:46 (99), 07/03/2019 12:33 (6), 01/03/2025 19:14 (16), 07/04/2025 17:24 (2)
Complete: 🔍
Cache ID: 216:9A1:103

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