Microsoft IIS 5.0 Content-Length Header denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.8$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Microsoft IIS 5.0. This vulnerability affects unknown code of the component Content-Length Header Handler. The manipulation leads to denial of service. This vulnerability is referenced as CVE-2001-1186. Furthermore, an exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Microsoft IIS 5.0 (Web Server) and classified as problematic. This issue affects an unknown code of the component Content-Length Header Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

Microsoft IIS 5.0 allows remote attackers to cause a denial of service via an HTTP request with a content-length value that is larger than the size of the request, which prevents IIS from timing out the connection.

The issue has been introduced in 02/17/2000. The weakness was published 12/11/2001 as not defined posting (Bugtraq). It is possible to read the advisory at securityfocus.com. The identification of this vulnerability is CVE-2001-1186. 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 are unknown but a public exploit is available.

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 663 days. During that time the estimated underground price was around $5k-$25k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 86283 (Microsoft IIS False Content-Length Field Denial of Service Vulnerability).

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the databases at X-Force (7691), Exploit-DB (21177), SecurityFocus (BID 3667†) and Vulnerability Center (SBV-3399†). Be aware that VulDB is the high quality source for 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

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

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

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EPSS Percentile: 🔍

Price Prediction: 🔍
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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: 🔍

Timelineinfo

02/17/2000 🔍
12/11/2001 +663 days 🔍
12/11/2001 +0 days 🔍
12/11/2001 +0 days 🔍
12/11/2001 +0 days 🔍
01/12/2004 +762 days 🔍
07/11/2014 +3833 days 🔍
09/27/2025 +4096 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: securityfocus.com⛔
Status: Confirmed

CVE: CVE-2001-1186 (🔍)
GCVE (CVE): GCVE-0-2001-1186
GCVE (VulDB): GCVE-100-17735
X-Force: 7691
SecurityFocus: 3667 - Microsoft IIS False Content-Length Field DoS Vulnerability
Vulnerability Center: 3399 - DoS in Microsoft IIS 5.0 via a HTTP Request With a Content-Length Value Longer than the Request Size, High

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

Entryinfo

Created: 07/11/2014 11:00
Updated: 09/27/2025 22:34
Changes: 07/11/2014 11:00 (41), 05/19/2019 09:40 (20), 01/28/2025 06:55 (27), 09/27/2025 22:34 (2)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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