CWE-1022 使用windows.opener访问指向不可信目标的web链接
Use of Web Link to Untrusted Target with window.opener Access
结构: Simple
Abstraction: Variant
状态: Incomplete
被利用可能性: Medium
基本描述
The web application produces links to untrusted external sites outside of its sphere of control, but it does not properly prevent the external site from modifying security-critical properties of the window.opener object, such as the location property.
扩展描述
When a user clicks a link to an external site ("target"), the target="_blank" attribute causes the target site's contents to be opened in a new window or tab, which runs in the same process as the original page. The window.opener object records information about the original page that offered the link. If an attacker can run script on the target page, then they could read or modify certain properties of the window.opener object, including the location property - even if the original and target site are not the same origin. An attacker can modify the location property to automatically redirect the user to a malicious site, e.g. as part of a phishing attack. Since this redirect happens in the original window/tab - which is not necessarily visible, since the browser is focusing the display on the new target page - the user might not notice any suspicious redirection.
相关缺陷
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cwe_Nature: ChildOf cwe_CWE_ID: 266 cwe_View_ID: 699 cwe_Ordinal: Primary
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cwe_Nature: ChildOf cwe_CWE_ID: 266 cwe_View_ID: 1000 cwe_Ordinal: Primary
适用平台
Language: {'cwe_Name': 'JavaScript', 'cwe_Prevalence': 'Often'}
Paradigm: {'cwe_Name': 'Web Based', 'cwe_Prevalence': 'Often'}
常见的影响
| 范围 | 影响 | 注释 |
|---|---|---|
| Confidentiality | Alter Execution Logic | The user may be redirected to an untrusted page that contains undesired content or malicious script code. |
可能的缓解方案
Architecture and Design
策略:
Specify in the design that any linked external document must not be granted access to the location object of the calling page.
Implementation
策略:
When creating a link to an external document using the tag with a defined target, for example "_blank" or a named frame, provide the rel attribute with a value "noopener noreferrer". If opening the external document in a new window via javascript, then reset the opener by setting it equal to null.
Implementation
策略: Do not use "_blank" targets. However, this can affect the usability of your application.
示例代码
例
In this example, the application opens a link in a named window/tab without taking precautions to prevent the called page from tampering with the calling page's location in the browser.
There are two ways that this weakness is commonly seen. The first is when the application generates an <a> tag is with target="_blank" to point to a target site:
bad HTML
If the attacker offers a useful page on this link (or compromises a trusted, popular site), then a user may click on this link. However, the attacker could use scripting code to modify the window.opener's location property to redirect the application to a malicious, attacker-controlled page - such as one that mimics the look and feel of the original application and convinces the user to re-enter authentication credentials, i.e. phishing:
attack JavaScript
To mitigate this type of weakness, some browsers support the "rel" attribute with a value of "noopener", which sets the window.opener object equal to null. Another option is to use the "rel" attribute with a value of "noreferrer", which in essence does the same thing.
good HTML
A second way that this weakness is commonly seen is when opening a new site directly within JavaScript. In this case, a new site is opened using the window.open() function.
bad JavaScript
To mitigate this, set the window.opener object to null.
good JavaScript
newWindow.opener = null;