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CWE WEAKNESSES  /  CWE-940

CWE-940

Improper Verification of Source of a Communication Channel

Base

What it is

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.

Impact

Access Control, OtherGain Privileges or Assume Identity, Varies by Context, Bypass Protection Mechanism

Mitigations

  • [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 interf

Real-world CVE examples

  • CVE-2025-3651 — desktop product does not properly verify the source of a communication channel, allowing command execution
  • CVE-2000-1218 — DNS server can accept DNS updates from hosts that it did not query, leading to cache poisoning
  • CVE-2005-0877 — DNS server can accept DNS updates from hosts that it did not query, leading to cache poisoning
  • CVE-2001-1452 — DNS server caches glue records received from non-delegated name servers

Related weaknesses

Test & detect

Browse all common weaknesses, check related exploited CVEs, or map to ATT&CK techniques.

Source: MITRE CWE. View on cwe.mitre.org →

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