CWE-639Authorization Bypass Through User-Controlled Key

Description

The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

[object Object]

Common consequences

• Access Control→Bypass Protection Mechanism
  Access control checks for specific user data or functionality can be bypassed.
• Access Control→Gain Privileges or Assume Identity
  Horizontal escalation of privilege is possible (one user can view/modify information of another user).
• Access Control→Gain Privileges or Assume Identity
  Vertical escalation of privilege is possible if the user-controlled key is actually a flag that indicates administrator status, allowing the attacker to gain administrative access.

Potential mitigations

• Architecture and Design
  For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
• Architecture and Design,Implementation
  Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
• Architecture and Design
  Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.

Related CWEs

Recent CVEs classified under this CWE