Microsoft IIS 4.0 ism.dll privileges management

CVSS Meta Temp Score
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CTI Interest Score
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3.6$0-$5k2.22

Summaryinfo

A vulnerability has been found in Microsoft IIS 4.0 and classified as problematic. This affects an unknown function in the library /scripts/iisadmin/ism.dll. Performing a manipulation results in privileges management. This vulnerability is identified as CVE-1999-1538. Additionally, an exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Microsoft IIS 4.0 (Web Server). It has been classified as problematic. This affects an unknown part in the library /scripts/iisadmin/ism.dll. The manipulation with an unknown input leads to a privileges management vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality. The summary by CVE is:

When IIS 2 or 3 is upgraded to IIS 4, ism.dll is inadvertently left in /scripts/iisadmin, which does not restrict access to the local machine and allows an unauthorized user to gain access to sensitive server information, including the Administrator's password.

The weakness was released 01/14/1999 by David Litchfield (nemo) as not defined posting (Bugtraq). It is possible to read the advisory at marc.theaimsgroup.com. This vulnerability is uniquely identified as CVE-1999-1538. The exploitability is told to be easy. Attacking locally is a requirement. No form of authentication is needed for exploitation. Technical details and a public exploit are known. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 10358 (Microsoft IIS /iisadmin Unrestricted Access), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Web Servers and running in the context r. The commercial vulnerability scanner Qualys is able to test this issue with plugin 10225 (Microsoft NT IIS 4 Remote Web-Based Administration Vulnerability).

Upgrading to version 5.0 eliminates this vulnerability. Attack attempts may be identified with Snort ID 993. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 1050.

The vulnerability is also documented in the databases at X-Force (7566), Exploit-DB (19147), Tenable (10358), SecurityFocus (BID 189†) and Vulnerability Center (SBV-470†). Entry connected to this vulnerability is available at VDB-14450. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Not Affected

  • Microsoft IIS 2.0/3.0

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.0
VulDB Meta Temp Score: 3.6

VulDB Base Score: 4.0
VulDB Temp Score: 3.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: Partially
Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 10358
Nessus Name: Microsoft IIS /iisadmin Unrestricted Access
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

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

Snort ID: 993
Snort Message: SERVER-IIS iisadmin access
Snort Class: 🔍

Suricata ID: 2100993
Suricata Class: 🔍
Suricata Message: 🔍

TippingPoint: 🔍
SourceFire IPS: 🔍
PaloAlto IPS: 🔍

Timelineinfo

01/14/1999 🔍
01/14/1999 +0 days 🔍
01/14/1999 +0 days 🔍
01/14/1999 +0 days 🔍
04/01/2000 +443 days 🔍
12/22/2002 +995 days 🔍
06/20/2014 +4198 days 🔍
04/18/2026 +4320 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: marc.theaimsgroup.com
Researcher: David Litchfield (nemo)
Status: Confirmed

CVE: CVE-1999-1538 (🔍)
GCVE (CVE): GCVE-0-1999-1538
GCVE (VulDB): GCVE-100-14451
X-Force: 7566
SecurityFocus: 189 - NT IIS4 Remote Web-Based Administration Vulnerability
Vulnerability Center: 470 - Microsoft IIS 4 Remote Web-Based Administration Reveals Sensitive Information, Low

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

Entryinfo

Created: 06/20/2014 12:55
Updated: 04/18/2026 04:38
Changes: 06/20/2014 12:55 (80), 05/07/2019 06:56 (1), 02/16/2025 05:24 (27), 10/20/2025 02:38 (2), 04/18/2026 04:38 (1)
Complete: 🔍
Cache ID: 216::103

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

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