Microsoft Internet Explorer 3.02/4.0/4.01 mk: Protocol Long URL memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Microsoft Internet Explorer 3.02/4.0/4.01. The affected element is an unknown function of the component mk: Protocol Handler. The manipulation as part of Long URL leads to memory corruption. This vulnerability is documented as CVE-1999-1094. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Microsoft Internet Explorer 3.02/4.0/4.01 (Web Browser). This issue affects an unknown code of the component mk: Protocol Handler. The manipulation as part of a Long URL leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Buffer overflow in Internet Explorer 4.01 and earlier allows remote attackers to execute arbitrary commands via a long URL with the "mk:" protocol, aka the "MK Overrun security issue."

The weakness was released 12/31/1999 as confirmed knowledge base article (Website). It is possible to read the advisory at support.microsoft.com. The identification of this vulnerability is CVE-1999-1094. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 5.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at X-Force (917). marc.theaimsgroup.com is providing further details. Entries connected to this vulnerability are available at VDB-15194 and VDB-15219. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: 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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Internet Explorer 5.0

Timelineinfo

12/31/1999 🔍
12/31/1999 +0 days 🔍
06/22/2014 +5287 days 🔍
04/20/2026 +4320 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: support.microsoft.com
Status: Confirmed

CVE: CVE-1999-1094 (🔍)
GCVE (CVE): GCVE-0-1999-1094
GCVE (VulDB): GCVE-100-15131
X-Force: 917 - Microsoft Internet Explorer MK overrun

Misc.: 🔍
See also: 🔍

Entryinfo

Created: 06/22/2014 16:50
Updated: 04/20/2026 03:31
Changes: 06/22/2014 16:50 (44), 04/07/2017 12:06 (12), 04/20/2026 03:31 (15)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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