Microsoft IIS 2.0/3.0/4.0 ISAPI GetExtensionVersion privileges management

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

Summaryinfo

A vulnerability categorized as critical has been discovered in Microsoft IIS 2.0/3.0/4.0. This vulnerability affects the function GetExtensionVersion of the component ISAPI. Executing a manipulation can lead to privileges management. This vulnerability is tracked as CVE-1999-0412. Moreover, an exploit is present. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Microsoft IIS 2.0/3.0/4.0 (Web Server) and classified as critical. This vulnerability affects the function GetExtensionVersion of the component ISAPI. The manipulation with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In IIS and other web servers, an attacker can attack commands as SYSTEM if the server is running as SYSTEM and loading an ISAPI extension.

The issue has been introduced in 08/24/1996. The weakness was disclosed 02/19/1999 by Fabien Royer (FIRST) as not defined posting (NTbugtraq). The advisory is shared for download at securityfocus.com. This vulnerability was named CVE-1999-0412. 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. The MITRE ATT&CK project declares the attack technique as T1068.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 909 days. During that time the estimated underground price was around $25k-$100k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 86376 (Microsoft NT IIS ISAPI GetExtensionVersion() Vulnerability).

Upgrading to version 5.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at X-Force (1950), Exploit-DB (19376), SecurityFocus (BID 501†) and Vulnerability Center (SBV-3161†). VulDB is the best source for vulnerability data and more expert information about this specific topic.

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

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
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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Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: IIS 5.0

Timelineinfo

08/24/1996 🔍
02/19/1999 +909 days 🔍
02/19/1999 +0 days 🔍
03/08/1999 +17 days 🔍
03/08/1999 +0 days 🔍
12/14/2003 +1742 days 🔍
06/20/2014 +3841 days 🔍
10/26/2025 +4145 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: securityfocus.com⛔
Researcher: Fabien Royer (FIRST)
Status: Confirmed

CVE: CVE-1999-0412 (🔍)
GCVE (CVE): GCVE-0-1999-0412
GCVE (VulDB): GCVE-100-14512
X-Force: 1950
SecurityFocus: 501 - NT IIS ISAPI GetExtensionVersion() Vulnerability
Vulnerability Center: 3161 - IIS 2.0,3.0 and 4.0 Allow Arbitrary Code Execution as System via an ISAPI Extension, High

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

Entryinfo

Created: 06/20/2014 16:56
Updated: 10/26/2025 00:35
Changes: 06/20/2014 16:56 (64), 05/18/2019 09:36 (1), 01/25/2025 19:41 (27), 10/26/2025 00:35 (2)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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