Vulnerabilities > CVE-2009-1122 - Improper Authentication vulnerability in Microsoft Internet Information Services 5.0
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
PARTIAL Integrity impact
PARTIAL Availability impact
PARTIAL Summary
The WebDAV extension in Microsoft Internet Information Services (IIS) 5.0 on Windows 2000 SP4 does not properly decode URLs, which allows remote attackers to bypass authentication, and possibly read or create files, via a crafted HTTP request, aka "IIS 5.0 WebDAV Authentication Bypass Vulnerability," a different vulnerability than CVE-2009-1535.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 1 | |
| OS | 1 |
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Authentication Abuse An attacker obtains unauthorized access to an application, service or device either through knowledge of the inherent weaknesses of an authentication mechanism, or by exploiting a flaw in the authentication scheme's implementation. In such an attack an authentication mechanism is functioning but a carefully controlled sequence of events causes the mechanism to grant access to the attacker. This attack may exploit assumptions made by the target's authentication procedures, such as assumptions regarding trust relationships or assumptions regarding the generation of secret values. This attack differs from Authentication Bypass attacks in that Authentication Abuse allows the attacker to be certified as a valid user through illegitimate means, while Authentication Bypass allows the user to access protected material without ever being certified as an authenticated user. This attack does not rely on prior sessions established by successfully authenticating users, as relied upon for the "Exploitation of Session Variables, Resource IDs and other Trusted Credentials" attack patterns.
- Exploiting Trust in Client (aka Make the Client Invisible) An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
- Utilizing REST's Trust in the System Resource to Register Man in the Middle This attack utilizes a REST(REpresentational State Transfer)-style applications' trust in the system resources and environment to place man in the middle once SSL is terminated. Rest applications premise is that they leverage existing infrastructure to deliver web services functionality. An example of this is a Rest application that uses HTTP Get methods and receives a HTTP response with an XML document. These Rest style web services are deployed on existing infrastructure such as Apache and IIS web servers with no SOAP stack required. Unfortunately from a security standpoint, there frequently is no interoperable identity security mechanism deployed, so Rest developers often fall back to SSL to deliver security. In large data centers, SSL is typically terminated at the edge of the network - at the firewall, load balancer, or router. Once the SSL is terminated the HTTP request is in the clear (unless developers have hashed or encrypted the values, but this is rare). The attacker can utilize a sniffer such as Wireshark to snapshot the credentials, such as username and password that are passed in the clear once SSL is terminated. Once the attacker gathers these credentials, they can submit requests to the web service provider just as authorized user do. There is not typically an authentication on the client side, beyond what is passed in the request itself so once this is compromised, then this is generally sufficient to compromise the service's authentication scheme.
- Man in the Middle Attack This type of attack targets the communication between two components (typically client and server). The attacker places himself in the communication channel between the two components. Whenever one component attempts to communicate with the other (data flow, authentication challenges, etc.), the data first goes to the attacker, who has the opportunity to observe or alter it, and it is then passed on to the other component as if it was never intercepted. This interposition is transparent leaving the two compromised components unaware of the potential corruption or leakage of their communications. The potential for Man-in-the-Middle attacks yields an implicit lack of trust in communication or identify between two components.
Metasploit
description This module attempts to to bypass authentication using the WebDAV IIS6 Unicode vulnerability discovered by Kingcope. The vulnerability appears to be exploitable where WebDAV is enabled on the IIS6 server, and any protected folder requires either Basic, Digest or NTLM authentication. id MSF:AUXILIARY/SCANNER/HTTP/MS09_020_WEBDAV_UNICODE_BYPASS last seen 2020-01-10 modified 2017-11-08 published 2009-11-26 references reporter Rapid7 source https://github.com/rapid7/metasploit-framework/blob/master//modules/auxiliary/scanner/http/ms09_020_webdav_unicode_bypass.rb title MS09-020 IIS6 WebDAV Unicode Authentication Bypass description This module is based on et's HTTP Directory Scanner module, with one exception. Where authentication is required, it attempts to bypass authentication using the WebDAV IIS6 Unicode vulnerability discovered by Kingcope. The vulnerability appears to be exploitable where WebDAV is enabled on the IIS6 server, and any protected folder requires either Basic, Digest or NTLM authentication. id MSF:AUXILIARY/SCANNER/HTTP/DIR_WEBDAV_UNICODE_BYPASS last seen 2020-03-07 modified 2017-11-08 published 2010-02-01 references reporter Rapid7 source https://github.com/rapid7/metasploit-framework/blob/master//modules/auxiliary/scanner/http/dir_webdav_unicode_bypass.rb title MS09-020 IIS6 WebDAV Unicode Auth Bypass Directory Scanner
Msbulletin
| bulletin_id | MS09-020 |
| bulletin_url | |
| date | 2009-06-09T00:00:00 |
| impact | Elevation of Privilege |
| knowledgebase_id | 970483 |
| knowledgebase_url | |
| severity | Important |
| title | Vulnerabilities in Internet Information Services (IIS) Could Allow Elevation of Privilege |
Nessus
| NASL family | Windows : Microsoft Bulletins |
| NASL id | SMB_NT_MS09-020.NASL |
| description | Due to a flaw in the WebDAV extension for IIS, an anonymous, remote attacker may be able to bypass authentication by sending a specially crafted HTTP request and gain access to a protected location. |
| last seen | 2020-06-01 |
| modified | 2020-06-02 |
| plugin id | 39342 |
| published | 2009-06-10 |
| reporter | This script is Copyright (C) 2009-2018 Tenable Network Security, Inc. |
| source | https://www.tenable.com/plugins/nessus/39342 |
| title | MS09-020: Vulnerabilities in Internet Information Services (IIS) Could Allow Elevation of Privilege (970483) |
| code | |
Oval
| accepted | 2009-07-21T07:45:57.357-04:00 | ||||||||||||
| class | vulnerability | ||||||||||||
| contributors |
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| definition_extensions |
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| description | The WebDAV extension in Microsoft Internet Information Services (IIS) 5.0 on Windows 2000 SP4 does not properly decode URLs, which allows remote attackers to bypass authentication, and possibly read or create files, via a crafted HTTP request, aka "IIS 5.0 WebDAV Authentication Bypass Vulnerability," a different vulnerability than CVE-2009-1535. | ||||||||||||
| family | windows | ||||||||||||
| id | oval:org.mitre.oval:def:5861 | ||||||||||||
| status | accepted | ||||||||||||
| submitted | 2009-06-15T14:00:00 | ||||||||||||
| title | IIS 5.0 WebDAV Authentication Bypass Vulnerability | ||||||||||||
| version | 36 |
Seebug
| bulletinFamily | exploit |
| description | BUGTRAQ ID: 35232 CVE(CAN) ID: CVE-2009-1122 Microsoft Internet信息服务（IIS）是Microsoft Windows自带的一个网络信息服务器，其中包含HTTP服务功能。 IIS的WebDAV扩展没有正确解码特制请求的URL，导致WebDAV在处理该请求时应用不正确的配置。如果应用的配置允许匿名访问，则特制的请求可以绕过身份验证。 请注意IIS在配置的匿名用户帐户的安全上下文中仍会处理该请求，因此此漏洞不能用于绕过NTFS ACL，文件系统ACL对匿名用户帐户强加的限制将仍然执行。 Microsoft IIS 5.0 临时解决方法： * 禁用WebDAV。 * 更改文件系统ACL拒绝对匿名用户账号访问。 厂商补丁： Microsoft --------- Microsoft已经为此发布了一个安全公告（MS09-020）以及相应补丁: MS09-020：Vulnerabilities in Internet Information Services (IIS) Could Allow Elevation of Privilege (970483) 链接：<a href="http://www.microsoft.com/technet/security/Bulletin/MS09-020.mspx?pf=true" target="_blank" rel=external nofollow>http://www.microsoft.com/technet/security/Bulletin/MS09-020.mspx?pf=true</a> 补丁下载： <a href="http://www.microsoft.com/downloads/details.aspx?familyid=8515a294-4f25-4dc5-860a-e7ad9b6c1c01" target="_blank" rel=external nofollow>http://www.microsoft.com/downloads/details.aspx?familyid=8515a294-4f25-4dc5-860a-e7ad9b6c1c01</a> |
| id | SSV:11603 |
| last seen | 2017-11-19 |
| modified | 2009-06-13 |
| published | 2009-06-13 |
| reporter | Root |
| title | Microsoft IIS 5.0 WebDAV绕过认证漏洞(MS09-020) |
References
- http://www.attrition.org/pipermail/vim/2009-June/002192.html
- http://www.securityfocus.com/bid/35232
- http://www.securitytracker.com/id?1022358
- http://www.us-cert.gov/cas/techalerts/TA09-160A.html
- http://www.vupen.com/english/advisories/2009/1539
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/2009/ms09-020
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5861