发布时间 :1999-09-01 00:00:00
修订时间 :2008-09-09 00:00:00

[原文]The "download behavior" in Internet Explorer 5 allows remote attackers to read arbitrary files via a server-side redirect.


        Internet Explorer 5版本的“download behavior”存在漏洞。远程攻击者可以借助服务器端重定向读取任意文件。

- CVSS (基础分值)

CVSS分值: 5 [中等(MEDIUM)]
机密性影响: PARTIAL [很可能造成信息泄露]
完整性影响: NONE [不会对系统完整性产生影响]
可用性影响: NONE [对系统可用性无影响]
攻击复杂度: LOW [漏洞利用没有访问限制 ]
攻击向量: [--]
身份认证: NONE [漏洞利用无需身份认证]

- CWE (弱点类目)

CWE-94 [对生成代码的控制不恰当(代码注入)]

- CPE (受影响的平台与产品)


- OVAL (用于检测的技术细节)


- 官方数据库链接
(官方数据源) MITRE
(官方数据源) NVD
(官方数据源) CNNVD

- 其它链接及资源
(UNKNOWN)  MS  MS99-040
(UNKNOWN)  CIAC  K-002;%5BLN%5D;Q242542
(UNKNOWN)  MSKB  Q242542

- 漏洞信息

中危 其他
1999-09-01 00:00:00 2005-10-12 00:00:00
        Internet Explorer 5版本的“download behavior”存在漏洞。远程攻击者可以借助服务器端重定向读取任意文件。

- 公告与补丁

        Microsoft has developed a patch for this problem. It is available at either of the following locations

- 漏洞信息 (19530)

MS IE 5.0 Download Behavior Vulnerability (EDBID:19530)
windows remote
1999-09-27 Verified
0 Georgi Guninski
N/A [点击下载]
Microsoft Internet Explorer 5.0 for Windows 95/Windows 98/Windows NT 4 Download Behavior Vulnerability


The "download behavior" feature of Microsoft's Internet Explorer 5 may allow a malicious web site operator to read files on an IE5 client computer or on a computer that is in the client's 'Local Intranet' web content zone.

IE5 introduced a new feature called DHTML Behaviors. DHTML Behaviors allow web developers to encapsulate methods, properties and events that can then be applied to HTML and XML elements. IE5 comes with set of built-in DHTML behaviors. One of them is the "#default#download" behaviors. This behavior defines a new Javascript method called "startDownload" that takes two parameters, the file to download and a function to call once the file has been downloaded.

By default the "startDownload" method checks that the file to be downloaded is in the same web content zone as the file calling the method. When both the file to be downloaded and the file executing the behavior are in the same security zone, the client will safely download the requested file and subsequently perform the specified function.

A malicious web site owner may bypass this security restriction and force an IE5 client to both read and perform a follow-up action on the contents of a local file or files in other security zones. This action may include sending the contents of the file back to the malicious web site operator.

Here's how it works:

1: An IE5 client visits a malicious website and loads a web page containing a client side scripting that makes use of the "#default#download" behavior.

2: The client side script calls the "startDownload" method and passes it the URL of a file to download and a function to call with the contents of the file once the file is finished downloading.

3. The startDownload method verifies that the URL is in fact in the same zone as the malicious web server.

4: The startDownload method begins the download, requesting the URL specified in step 2 from a malicious web server.

5: The malicious web server send an HTTP redirect to some other file in any security zone including local files on the IE5 client machine (for example: c:\winnt\repair\sam._).

6: startDownload reads the file and executes the function specified in step 2 on that file's content.

The malicious web server has now bypassed the security restrictions outlined earlier by successfully forcing the client to load and act upon a file that resides in a web content zone different than that of the malicious web server. This can all be done transparently to the end user.

This vulnerability cannot be used to delete or modify files on the vulnerable IE5 client. The vulnerability can only retrieve text files or small parts of binary files.

function doit(s)
alert ("Here is your file:\n"+s);
<A ID="oD" STYLE="behavior:url(#default#download)"
doit)">Click here to read C:\AUTOEXEC.BAT</A>.

<!-- ("" just does a HTTP redirect to file://c:/autoexec.bat) -->

- 漏洞信息

Microsoft IE "download behavior" Server Side Redirect Arbitrary File Access
Remote / Network Access Information Disclosure
Loss of Confidentiality Patch / RCS
Exploit Public

- 漏洞描述

Microsoft Internet Explorer (MSIE) contains a flaw that may lead to an unauthorized information disclosure. The issue is triggered when a user visits a malicious web site with their browser while having active scripting enabled. The malicious web site can return a response that overwrites the download URL via a server side redirect, which will disclose local files on the user's system resulting in a loss of confidentiality.

- 时间线

1999-09-28 Unknow
Unknow Unknow

- 解决方案

Microsoft has released a patch to address this issue. Additionally, it is possible to correct the flaw by implementing the following workaround(s): disable active scripting

- 相关参考

- 漏洞作者