The product establishes a communication channel to handle an incoming request that has been initiated by an actor, but it does not properly verify that the request is coming from the expected origin.
When an attacker can successfully establish a communication channel from an untrusted origin, the attacker may be able to gain privileges and access unexpected functionality.

Primary

Architecture and Design

Implementation
REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Access Control
Other
Gain Privileges or Assume Identity
Varies by Context
Bypass Protection Mechanism
An attacker can access any functionality that is inadvertently accessible to the source.

Architecture and Design

Use a mechanism that can validate the identity of the source, such as a certificate, and validate the integrity of data to ensure that it cannot be modified in transit using an Adversary-in-the-Middle (AITM) attack.
When designing functionality of actions in the URL scheme, consider whether the action should be accessible to all mobile applications, or if an allowlist of applications to interface with is appropriate.

This Android application will remove a user account when it receives an intent to do so:

IntentFilter filter = new IntentFilter("com.example.RemoveUser");MyReceiver receiver = new MyReceiver();registerReceiver(receiver, filter);
public class DeleteReceiver extends BroadcastReceiver {@Overridepublic void onReceive(Context context, Intent intent) {int userID = intent.getIntExtra("userID");destroyUserData(userID);}}

This application does not check the origin of the intent, thus allowing any malicious application to remove a user. Always check the origin of an intent, or create an allowlist of trusted applications using the manifest.xml file.

These Android and iOS applications intercept URL loading within a WebView and perform special actions if a particular URL scheme is used, thus allowing the Javascript within the WebView to communicate with the application:

// Android
@Overridepublic boolean shouldOverrideUrlLoading(WebView view, String url){
if (url.substring(0,14).equalsIgnoreCase("examplescheme:")){if(url.substring(14,25).equalsIgnoreCase("getUserInfo")){writeDataToView(view, UserData);return false;}else{return true;}}
}

// iOS
-(BOOL) webView:(UIWebView *)exWebView shouldStartLoadWithRequest:(NSURLRequest *)exRequest navigationType:(UIWebViewNavigationType)exNavigationType{
NSURL *URL = [exRequest URL];if ([[URL scheme] isEqualToString:@"exampleScheme"]){
NSString *functionString = [URL resourceSpecifier];if ([functionString hasPrefix:@"specialFunction"]){

// Make data available back in webview.
UIWebView *webView = [self writeDataToView:[URL query]];
}return NO;
}return YES;
}

A call into native code can then be initiated by passing parameters within the URL:

window.location = examplescheme://method?parameter=value

Because the application does not check the source, a malicious website loaded within this WebView has the same access to the API as a trusted site.

CVE-2000-1218
DNS server can accept DNS updates from hosts that it did not query, leading to cache poisoning
https://www.cve.org/CVERecord?id=CVE-2000-1218

CVE-2005-0877
DNS server can accept DNS updates from hosts that it did not query, leading to cache poisoning
https://www.cve.org/CVERecord?id=CVE-2005-0877

CVE-2001-1452
DNS server caches glue records received from non-delegated name servers
https://www.cve.org/CVERecord?id=CVE-2001-1452

Allowed
This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

While many access control issues involve authenticating the user, this weakness is more about authenticating the actual source of the communication channel itself; there might not be any "user" in such cases.

CWE Content Team
MITRE
2014-02-13
2.6
2014-02-19

CWE Content Team
MITRE
2017-11-08
updated Modes_of_Introduction, References, Relationships

CWE Content Team
MITRE
2019-06-20
updated Related_Attack_Patterns

CWE Content Team
MITRE
2020-02-24
updated Applicable_Platforms, Potential_Mitigations, Relationships

CWE Content Team
MITRE
2020-06-25
updated Demonstrative_Examples, Potential_Mitigations

CWE Content Team
MITRE
2021-07-20
updated Potential_Mitigations

CWE Content Team
MITRE
2021-10-28
updated Relationships

CWE Content Team
MITRE
2022-10-13
updated Relationships

CWE Content Team
MITRE
2023-01-31
updated Description, Related_Attack_Patterns

CWE Content Team
MITRE
2023-04-27
updated Relationships

CWE Content Team
MITRE
2023-06-29
updated Mapping_Notes, Relationships

CWE Content Team
MITRE
2024-11-19
4.16
2024-11-19
updated References

CWE Content Team
MITRE
2025-12-11
4.19
2025-12-11
updated Common_Consequences, Relationships, Weakness_Ordinalities