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CWE WEAKNESSES  /  CWE-99

CWE-99

Improper Control of Resource Identifiers ('Resource Injection')

Class EXPLOIT LIKELIHOOD: HIGH

What it is

The product receives input from an upstream component, but it does not restrict or incorrectly restricts the input before it is used as an identifier for a resource that may be outside the intended sphere of control.

A resource injection issue occurs when the following two conditions are met:1. An attacker can specify the identifier used to access a system resource. For example, an attacker might be able to specify part of the name of a file to be opened or a port number to be used.1. By specifying the resource, the attacker gains a capability that would not otherwise be permitted. For example, the program may give the attacker the ability to overwrite the specified file, run with a configuration controlled by the attacker, or transmit sensitive information to a third-party server.This may enable an attacker to access or modify otherwise protected system resources.

Impact

Confidentiality, IntegrityRead Application Data, Modify Application Data, Read Files or Directories, Modify Files or Directories

Mitigations

  • [Implementation]Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.When performing input validation, consider all potentially relevant properties, including length, type of input, the full r

Real-world CVE examples

  • CVE-2013-4787 — chain: mobile OS verifies cryptographic signature of file in an archive, but then installs a different file with the same name that is also listed in the archiv

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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