Microsoft Internet Explorer 6 urlmon.dll heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Microsoft Internet Explorer 6. This impacts an unknown function in the library urlmon.dll. Such manipulation leads to heap-based overflow. This vulnerability is listed as CVE-2006-3873. The attack may be performed from remote. There is no available exploit. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Microsoft Internet Explorer 6 (Web Browser). It has been rated as critical. Affected by this issue is an unknown function in the library urlmon.dll. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to 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(). Impacted is confidentiality, integrity, and availability. CVE summarizes:

Heap-based buffer overflow in URLMON.DLL in Microsoft Internet Explorer 6 SP1 on Windows 2000 and XP SP1, with versions the MS06-042 patch before 20060912, allows remote attackers to cause a denial of service (crash) or execute arbitrary code via a long URL in a GZIP-encoded website that was the target of an HTTP redirect, due to an incomplete fix for CVE-2006-3869.

The issue has been introduced in 03/22/2001. The weakness was presented 08/24/2006 by Derek Soeder (DiGiT) with eEye Digital Security as MS06-042 as confirmed bulletin (Technet). The advisory is shared for download at microsoft.com. This vulnerability is handled as CVE-2006-3873 since 07/26/2006. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 1965 days. During that time the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 22184 (MS06-042: Cumulative Security Update for Internet Explorer (918899)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows : Microsoft Bulletins. The commercial vulnerability scanner Qualys is able to test this issue with plugin 100036 (Microsoft Cumulative Security Update for Internet Explorer (MS06-042)).

Upgrading to version Sp1 eliminates this vulnerability. Applying the patch MS06-042 is able to eliminate this problem. The bugfix is ready for download at microsoft.com. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published before and not just after the disclosure of the vulnerability. Attack attempts may be identified with Snort ID 16033. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 13775.

The vulnerability is also documented in the databases at X-Force (28893), Tenable (22184), SecurityFocus (BID 19987†), OSVDB (30834†) and SecurityTracker (ID 1016839†). See VDB-1028, VDB-2344, VDB-2343 and VDB-2440 for similar entries. Once again VulDB remains the best source for vulnerability data.

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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: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

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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: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 22184
Nessus Name: MS06-042: Cumulative Security Update for Internet Explorer (918899)
Nessus File: 🔍
Nessus Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Upgrade: Internet Explorer Sp1
Patch: MS06-042

Snort ID: 16033
TippingPoint: 🔍

McAfee IPS: 🔍
McAfee IPS Version: 🔍

PaloAlto IPS: 🔍
Fortigate IPS: 🔍

Timelineinfo

03/22/2001 🔍
07/26/2006 +1952 days 🔍
08/08/2006 +13 days 🔍
08/24/2006 +16 days 🔍
09/12/2006 +18 days 🔍
09/12/2006 +0 days 🔍
09/12/2006 +0 days 🔍
09/13/2006 +1 days 🔍
09/13/2006 +0 days 🔍
12/12/2006 +90 days 🔍
03/12/2015 +3011 days 🔍
06/21/2025 +3754 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: MS06-042
Researcher: Derek Soeder (DiGiT)
Organization: eEye Digital Security
Status: Confirmed

CVE: CVE-2006-3873 (🔍)
GCVE (CVE): GCVE-0-2006-3873
GCVE (VulDB): GCVE-100-32228
X-Force: 28893
SecurityFocus: 19987 - Microsoft Internet Explorer HTTP 1.1 and Compression Long URI Buffer Overflow Variant Vulnerability
OSVDB: 30834 - Microsoft IE URLMON.DLL Long URL HTTP Redirect Overflow
SecurityTracker: 1016839 - Microsoft Internet Explorer URLMON.DLL Buffer Overflow Lets Remote Users Execute Arbitrary Code
Vulnerability Center: 12679 - [MS06-042] Microsoft Internet Explorer with MS06-042 Patch before 20060912 Long URL Vulnerability, Medium

See also: 🔍

Entryinfo

Created: 03/12/2015 15:51
Updated: 06/21/2025 19:57
Changes: 03/12/2015 15:51 (71), 04/07/2017 12:08 (19), 06/21/2025 19:57 (17)
Complete: 🔍
Cache ID: 216:1E0:103

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