Microsoft IIS 2.0/3.0/4.0/5.0 IISAPI Extension perl.exe information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability has been found in Microsoft IIS 2.0/3.0/4.0/5.0 and classified as problematic. Affected by this vulnerability is an unknown functionality of the file perl.exe of the component IISAPI Extension. The manipulation leads to information disclosure. This vulnerability is referenced as CVE-1999-0450. Furthermore, an exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Microsoft IIS 2.0/3.0/4.0/5.0 (Web Server). This issue affects an unknown part of the file perl.exe of the component IISAPI Extension. The manipulation with an unknown input leads to a information disclosure vulnerability. Using CWE to declare the problem leads to CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. Impacted is confidentiality. The summary by CVE is:

In IIS, an attacker could determine a real path using a request for a non-existent URL that would be interpreted by Perl (perl.exe).

The issue has been introduced in 08/24/1996. The weakness was published 01/26/1999 by David Litchfield (FIRST) with NGSSoftware as not defined mailinglist post (NTBugtraq). The advisory is shared at securityfocus.com. The identification of this vulnerability is CVE-1999-0450. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known. MITRE ATT&CK project uses the attack technique T1592 for this issue.

The exploit is available 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 885 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 10120 (Microsoft IIS perl.exe HTTP Path Disclosure), 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 86032 (Microsoft IIS Absolute Path Disclosure Vulnerability).

Upgrading to version 6.0 eliminates this vulnerability. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 884.

The vulnerability is also documented in the databases at Exploit-DB (19152), Tenable (10120), SecurityFocus (BID 194†) and Vulnerability Center (SBV-403†). Similar entries are available at VDB-14467 and VDB-14466. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 4.8

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / 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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Nessus ID: 10120
Nessus Name: Microsoft IIS perl.exe HTTP Path Disclosure
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 6.0
TippingPoint: 🔍
PaloAlto IPS: 🔍
Fortigate IPS: 🔍

Timelineinfo

08/24/1996 🔍
01/26/1999 +885 days 🔍
01/26/1999 +0 days 🔍
01/26/1999 +0 days 🔍
01/26/1999 +0 days 🔍
06/22/1999 +147 days 🔍
12/17/2002 +1274 days 🔍
06/20/2014 +4203 days 🔍
10/26/2025 +4145 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: securityfocus.com⛔
Researcher: David Litchfield (FIRST)
Organization: NGSSoftware
Status: Confirmed

CVE: CVE-1999-0450 (🔍)
GCVE (CVE): GCVE-0-1999-0450
GCVE (VulDB): GCVE-100-14465
SecurityFocus: 194 - NT IIS IISAPI Extension Enumerate Root Web Server Directory Vulnerability
Vulnerability Center: 403 - NT IIS IISAPI Extension Enumerate Root Web Server Directory Vulnerability, Low

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

Entryinfo

Created: 06/20/2014 13:13
Updated: 10/26/2025 00:35
Changes: 06/20/2014 13:13 (78), 05/06/2019 16:52 (1), 02/16/2025 06:16 (27), 10/26/2025 00:35 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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