Microsoft IIS 5.0/5.1/6.0 Password Protection improper authentication

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Microsoft IIS 5.0/5.1/6.0. Affected is an unknown function of the component Password Protection. The manipulation results in improper authentication. This vulnerability was named CVE-2009-1535. In addition, an exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Microsoft IIS 5.0/5.1/6.0 (Web Server). It has been classified as critical. Affected is some unknown functionality of the component Password Protection. The manipulation with an unknown input leads to a improper authentication vulnerability. CWE is classifying the issue as CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

The WebDAV extension in Microsoft Internet Information Services (IIS) 5.1 and 6.0 allows remote attackers to bypass URI-based protection mechanisms, and list folders or read, create, or modify files, via a %c0%af (Unicode / character) at an arbitrary position in the URI, as demonstrated by inserting %c0%af into a "/protected/" initial pathname component to bypass the password protection on the protected\ folder, aka "IIS 5.1 and 6.0 WebDAV Authentication Bypass Vulnerability," a different vulnerability than CVE-2009-1122.

The issue has been introduced in 02/17/2000. The weakness was presented 06/10/2009 by kingcope (Website). The advisory is available at us-cert.gov. This vulnerability is traded as CVE-2009-1535 since 05/05/2009. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are unknown but a public exploit is available.

A public exploit has been developed in Ruby. The exploit is shared for download at securityfocus.com. It is declared as highly functional. The vulnerability was handled as a non-public zero-day exploit for at least 3378 days. During that time the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 38808 (Microsoft IIS WebDAV Unicode Request Directory Security Bypass), 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 86837 (Internet Information Services (IIS) Could Allow Elevation of Privilege (MS09-020)).

Upgrading eliminates this vulnerability. Furthermore it is possible to detect and prevent this kind of attack with TippingPoint and the filter 8137.

The vulnerability is also documented in the databases at X-Force (50768), Tenable (38808), SecurityFocus (BID 34993†), OSVDB (54555†) and Vulnerability Center (SBV-22026†). See VDB-37163, VDB-48554, VDB-48553 and VDB-48552 for similar entries. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.1
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.1
VulDB Temp Score: 7.7
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: Improper authentication
CWE: CWE-287
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Highly functional
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 38808
Nessus Name: Microsoft IIS WebDAV Unicode Request Directory Security Bypass
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 900567
OpenVAS Name: Microsoft IIS Security Bypass Vulnerability (970483)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

MetaSploit ID: dir_webdav_unicode_bypass.rb
MetaSploit Name: Web Site Crawler
MetaSploit File: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍
TippingPoint: 🔍

McAfee IPS: 🔍
McAfee IPS Version: 🔍

ISS Proventia IPS: 🔍
PaloAlto IPS: 🔍
Fortigate IPS: 🔍

Timelineinfo

02/17/2000 🔍
05/05/2009 +3365 days 🔍
05/15/2009 +10 days 🔍
05/15/2009 +0 days 🔍
05/17/2009 +2 days 🔍
05/18/2009 +1 days 🔍
06/10/2009 +23 days 🔍
06/10/2009 +0 days 🔍
03/17/2015 +2106 days 🔍
11/09/2025 +3890 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: us-cert.gov
Researcher: kingcope
Status: Confirmed

CVE: CVE-2009-1535 (🔍)
GCVE (CVE): GCVE-0-2009-1535
GCVE (VulDB): GCVE-100-48498

OVAL: 🔍

X-Force: 50768
SecurityFocus: 34993 - Microsoft IIS Unicode Requests to WebDAV Multiple Authentication Bypass Vulnerabilities
OSVDB: 54555 - Microsoft IIS WebDAV Unicode URI Request Authentication Bypass
Vulnerability Center: 22026 - [MS09-020] Microsoft IIS 5.0 / 5.1 / 6.0 WebDAV Folders Remote Authentication Bypass Vulnerability, Medium

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

Entryinfo

Created: 03/17/2015 23:38
Updated: 11/09/2025 20:14
Changes: 03/17/2015 23:38 (89), 09/03/2019 18:19 (3), 08/11/2021 14:37 (3), 11/09/2025 20:14 (16)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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