Description
The web application does not restrict or incorrectly restricts frame objects or UI layers that belong to another application or domain.
Potential Impact
Access Control
Gain Privileges or Assume Identity, Bypass Protection Mechanism, Read Application Data, Modify Application Data
Mitigations & Prevention
The use of X-Frame-Options allows developers of web content to restrict the usage of their application within the form of overlays, frames, or iFrames. The developer can indicate from which domains can frame the content. The concept of X-Frame-Options is well documented, but implementation of this protection mechanism is in development to cover gaps. There is a need for allowing frames from multiple domains.
A developer can use a "frame-breaker" script in each page that should not be framed. This is very helpful for legacy browsers that do not support X-Frame-Options security feature previously mentioned. It is also important to note that this tactic has been circumvented or bypassed. Improper usage of frames can persist in the web application through nested frames. The "frame-breaking" script does not intuitively account for multiple nested frames that can be presented to the us
This defense-in-depth technique can be used to prevent the improper usage of frames in web applications. It prioritizes the valid sources of data to be loaded into the application through the usage of declarative policies. Based on which implementation of Content Security Policy is in use, the developer should use the "frame-ancestors" directive or the "frame-src" directive to mitigate this weakness. Both directives allow for the placement of restrictions when it comes to allowing embedded conte
In addition to frames or iframes as previously mentioned, the web application is expected to place restrictions on whether it is allowed to be rendered within objects, embed, or applet elements.
Detection Methods
- Automated Static Analysis High — Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then sea
Real-World CVE Examples
| CVE ID | Description |
|---|---|
| CVE-2017-7440 | E-mail preview feature in a desktop application allows clickjacking attacks via a crafted e-mail message |
| CVE-2017-5697 | Hardware/firmware product has insufficient clickjacking protection in its web user interface |
| CVE-2017-4015 | Clickjacking in data-loss prevention product via HTTP response header. |
| CVE-2016-2496 | Tapjacking in permission dialog for mobile OS allows access of private storage using a partially-overlapping window. |
| CVE-2015-1241 | Tapjacking in web browser related to page navigation and touch/gesture events. |
| CVE-2017-0492 | System UI in mobile OS allows a malicious application to create a UI overlay of the entire screen to gain privileges. |
Related Weaknesses
Frequently Asked Questions
What is CWE-1021?
CWE-1021 (Improper Restriction of Rendered UI Layers or Frames) is a software weakness identified by MITRE's Common Weakness Enumeration. It is classified as a Base-level weakness. The web application does not restrict or incorrectly restricts frame objects or UI layers that belong to another application or domain.
How can CWE-1021 be exploited?
Attackers can exploit CWE-1021 (Improper Restriction of Rendered UI Layers or Frames) to gain privileges or assume identity, bypass protection mechanism, read application data, modify application data. This weakness is typically introduced during the Implementation phase of software development.
How do I prevent CWE-1021?
Key mitigations include: The use of X-Frame-Options allows developers of web content to restrict the usage of their application within the form of overlays, frames, or iFrames. The developer can indicate from which domains ca
What is the severity of CWE-1021?
CWE-1021 is classified as a Base-level weakness (Medium abstraction). It has been observed in 6 real-world CVEs.