The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate.
View on MITREIf a cross-domain policy file includes domains that should not be trusted, such as when using wildcards under a high-level domain, then the application could be attacked by these untrusted domains. In many cases, the attack can be launched without the victim even being aware of it.
With an overly permissive policy file, an attacker may be able to bypass the web browser's same-origin policy and conduct many of the same attacks seen in Cross-Site Scripting (CWE-79). An attacker can exploit the weakness to transfer private information from the victim's machine to the attacker, manipulate or steal cookies that may include session information, create malicious requests to a web site on behalf of the victim, or execute malicious code on the end user systems. Other damaging attacks include the disclosure of end user files, installation of Trojan horse programs, redirecting the user to some other page or site, running ActiveX controls (under Microsoft Internet Explorer) from sites that a user perceives as trustworthy, and modifying presentation of content.
Define a restrictive Content Security Policy [REF-1486] or cross-domain policy file.
Avoid using wildcards in the CSP / cross-domain policy file. Any domain matching the wildcard expression will be implicitly trusted, and can perform two-way interaction with the target server.
For Flash, modify crossdomain.xml to use meta-policy options such as 'master-only' or 'none' to reduce the possibility of an attacker planting extraneous cross-domain policy files on a server.
No detection method information available for this CWE.
These cross-domain policy files mean to allow Flash and Silverlight applications hosted on other domains to access its data:
Flash crossdomain.xml :
These cross-domain policy files mean to allow Flash and Silverlight applications hosted on other domains to access its data:
Flash crossdomain.xml :
Product has a Silverlight cross-domain policy that does not restrict access to another application, which allows remote attackers to bypass the Same Origin Policy.
View DetailsThe default Flash Cross Domain policies in a product allows remote attackers to access user files.
View DetailsChain: Adobe Flash Player does not sufficiently restrict the interpretation and usage of cross-domain policy files, which makes it easier for remote attackers to conduct cross-domain and cross-site scripting (XSS) attacks.
View DetailsChain: Adobe Flash Player and earlier does not properly interpret policy files, which allows remote attackers to bypass a non-root domain policy.
View DetailsChain: Adobe Flash Player does not properly handle unspecified encodings during the parsing of a cross-domain policy file, which allows remote web servers to bypass intended access restrictions via unknown vectors.
View DetailsCWE-942: Permissive Cross-domain Security Policy with Untrusted Domains is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The product uses a web-client protection mechanism such as a Content Security Policy (CSP) or cross-domain policy file, but the policy includes untrusted domains with which the web client is allowed to communicate. If a cross-domain policy file includes domains that should not be trusted, such as when using wildcards under a high-level domain, then the application could be attacked by these untrusted domains. In many cases, the attack can be launched without the victim even being aware of it.
If exploited, CWE-942 (Permissive Cross-domain Security Policy with Untrusted Domains) it can compromise Confidentiality, Integrity, Availability and Access Control, leading to outcomes such as Execute Unauthorized Code or Commands, Bypass Protection Mechanism, Read Application Data and Varies by Context.
Recommended mitigations for CWE-942 include: Define a restrictive Content Security Policy [REF-1486] or cross-domain policy file. Avoid using wildcards in the CSP / cross-domain policy file. Any domain matching the wildcard expression will be implicitly trusted, and can perform two-way interaction with the target server. For Flash, modify crossdomain.xml to use meta-policy options such as 'master-only' or 'none' to reduce the possibility of an attacker planting extraneous cross-domain policy files on a server.
CWE-942 commonly affects Not Language-Specific. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.
MITRE documents real CVEs mapped to CWE-942, including CVE-2012-2292, CVE-2014-2049, CVE-2007-6243, CVE-2008-4822 and CVE-2010-3636. You can look up the full details of each CVE, including CVSS scores and remediation guidance, on our CVE Lookup tool.
A CWE (Common Weakness Enumeration) like CWE-942 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.